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Computer Science -Assessing Processor Speed
We must also assess the speed at which a computer can process data. This essentially delineates the speed at which the computer processes information. The central processing unit (CPU) of a computer functions as its primary cognitive component. CPUs possess inbuilt clocks that measure the speed at which they execute individual mathematical operations. This is not a conventional clock, such as one often found in a household, that ticks every second. Computers process information at remarkable speeds, with their internal clocks oscillating billions of times each second.
The speed of a CPU is quantified by the frequency of its clock ticks, measured in hertz, with each hertz representing one tick. The clock in your home ticks once per second. The clock operates at one hertz, indicating one tick per second. Computer clocks are measured in hertz multiples. Early personal computers quantified clock speed in megahertz (MHz), representing millions of cycles per second. Contemporary computer processors operate at gigahertz (GHz), signifying billions of cycles per second. Each of the ticks of the computer's clock is referred to as a cycle. This concludes the three fundamental methods for measuring the speed and capacity of data, networks, and computers. Data storage on disks and in memory is quantified using bits and bytes. Network speed is quantified in bits per second. Computer processing speed is measured in hertz.
We must also assess the speed at which a computer can process data. This essentially delineates the speed at which the computer processes information. The central processing unit (CPU) of a computer functions as its primary cognitive component. CPUs possess inbuilt clocks that measure the speed at which they execute individual mathematical operations. This is not a conventional clock, such as one often found in a household, that ticks every second. Computers process information at remarkable speeds, with their internal clocks oscillating billions of times each second.
The speed of a CPU is quantified by the frequency of its clock ticks, measured in hertz, with each hertz representing one tick. The clock in your home ticks once per second. The clock operates at one hertz, indicating one tick per second. Computer clocks are measured in hertz multiples. Early personal computers quantified clock speed in megahertz (MHz), representing millions of cycles per second. Contemporary computer processors operate at gigahertz (GHz), signifying billions of cycles per second. Each of the ticks of the computer's clock is referred to as a cycle. This concludes the three fundamental methods for measuring the speed and capacity of data, networks, and computers. Data storage on disks and in memory is quantified using bits and bytes. Network speed is quantified in bits per second. Computer processing speed is measured in hertz.
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Conputer Science - Elucidate the fundamentals of computing.
Computers execute four fundamental operations on data: they receive input from users and devices, process data through computations and other functions, store data acquired from input and processing, and deliver output of their results.
Computer Operations
Every computing system executes four fundamental operations: acquiring input, storing data, processing data, and delivering output. This applies to laptops, desktop computers, servers, smartphones, tablets, and other specialized computing devices.
Input
Input refers to the information sent to a device to assist in task execution. User input is frequently received, and we present it in various methods. When utilizing a laptop or desktop computer, input may be provided through keyboard typing or mouse movement and clicking. On a tablet or smartphone, we often engage by touching or swiping the screen or utilizing voice commands. Input need not originate directly from an individual. Computers can receive input from other computers, stored data, or sensors. The thermostat in your residence functions as a computer. It obtains data from an integrated thermometer that indicates the present temperature in your residence. It also obtains input from inhabitants when they adjust the temperature setting on the thermostat display.
Processing
Processing refers to the computer's analysis of data and execution of operations on it. For instance, when a computer determines the overall cost of a customer order by aggregating the prices of individual items and calculating taxes and discounts, this exemplifies processing. Computers can additionally manipulate data using alternative methods. When a computer alters an image file, plays a video file saved on a disk, or forecasts the weather, these operations exemplify processing. In the majority of computer systems, processing is executed by a specialized chip known as the central processing unit (CPU).
Output
For a computer to be functional, it must possess a means of delivering output. The output is the computer's report on the results of its processing. Output may manifest in several forms. The most basic form of output involves displaying the outcomes of data processing on the screen for our perusal. A printer can be utilized to generate a physical record of output. Output may also manifest in alternative forms. A computer may utilize its output to teach another device on its operational procedures rather than presenting the results of its calculations for our review.
Storage
Upon receiving input, a computer can either store the data directly or process it prior to storage. Storage techniques enable computers to retain data for future use. Computers can store data in two distinct methods. They may retain certain data in volatile memory for rapid access, or they may transfer the data to a hard disk, cloud storage service, or alternative storage medium for more permanent retention.
Computers execute four fundamental operations on data: they receive input from users and devices, process data through computations and other functions, store data acquired from input and processing, and deliver output of their results.
Computer Operations
Every computing system executes four fundamental operations: acquiring input, storing data, processing data, and delivering output. This applies to laptops, desktop computers, servers, smartphones, tablets, and other specialized computing devices.
Input
Input refers to the information sent to a device to assist in task execution. User input is frequently received, and we present it in various methods. When utilizing a laptop or desktop computer, input may be provided through keyboard typing or mouse movement and clicking. On a tablet or smartphone, we often engage by touching or swiping the screen or utilizing voice commands. Input need not originate directly from an individual. Computers can receive input from other computers, stored data, or sensors. The thermostat in your residence functions as a computer. It obtains data from an integrated thermometer that indicates the present temperature in your residence. It also obtains input from inhabitants when they adjust the temperature setting on the thermostat display.
Processing
Processing refers to the computer's analysis of data and execution of operations on it. For instance, when a computer determines the overall cost of a customer order by aggregating the prices of individual items and calculating taxes and discounts, this exemplifies processing. Computers can additionally manipulate data using alternative methods. When a computer alters an image file, plays a video file saved on a disk, or forecasts the weather, these operations exemplify processing. In the majority of computer systems, processing is executed by a specialized chip known as the central processing unit (CPU).
Output
For a computer to be functional, it must possess a means of delivering output. The output is the computer's report on the results of its processing. Output may manifest in several forms. The most basic form of output involves displaying the outcomes of data processing on the screen for our perusal. A printer can be utilized to generate a physical record of output. Output may also manifest in alternative forms. A computer may utilize its output to teach another device on its operational procedures rather than presenting the results of its calculations for our review.
Storage
Upon receiving input, a computer can either store the data directly or process it prior to storage. Storage techniques enable computers to retain data for future use. Computers can store data in two distinct methods. They may retain certain data in volatile memory for rapid access, or they may transfer the data to a hard disk, cloud storage service, or alternative storage medium for more permanent retention.
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Computer Structure - Identify notation systems
Computers are engineered to store and process data in binary format; nevertheless, this format is frequently impractical or unsuitable for humans or software applications. Notational systems enable the utilization of binary data storage technology to represent numbers, language, and various data formats.
Data Storage
As we explore the realm of information technology, it is essential to comprehend how computers store and process data. Let us initiate the topic by addressing the fundamental units of storage within a computer system. Binary Information It is likely that you are aware that computers operate using binary data, which is represented solely by 0s and 1s. All operations within a computer system utilize combinations of zeros and ones. All elements, including the operating system, applications, Microsoft Word documents, and video files, are encoded in binary format. This is because computers can efficiently utilize this binary format to store data on disk, retain it in memory, or transmit it over a network. The fundamental unit of binary storage in any computer system is the bit. A bit is a solitary binary digit that can represent either 1 or 0. These are the sole two potential values for a bit. The numeral 2 and the letter Z cannot be represented in a bit. It can solely be a 1 or a 0.
Computers are engineered to store and process data in binary format; nevertheless, this format is frequently impractical or unsuitable for humans or software applications. Notational systems enable the utilization of binary data storage technology to represent numbers, language, and various data formats.
Data Storage
As we explore the realm of information technology, it is essential to comprehend how computers store and process data. Let us initiate the topic by addressing the fundamental units of storage within a computer system. Binary Information It is likely that you are aware that computers operate using binary data, which is represented solely by 0s and 1s. All operations within a computer system utilize combinations of zeros and ones. All elements, including the operating system, applications, Microsoft Word documents, and video files, are encoded in binary format. This is because computers can efficiently utilize this binary format to store data on disk, retain it in memory, or transmit it over a network. The fundamental unit of binary storage in any computer system is the bit. A bit is a solitary binary digit that can represent either 1 or 0. These are the sole two potential values for a bit. The numeral 2 and the letter Z cannot be represented in a bit. It can solely be a 1 or a 0.
When data is stored on a magnetic hard drive, the computer partitions the disk into billions of little places, each intended to accommodate a single bit. When the bit's value is 1, the computer assigns a magnetic charge to the corresponding position of that bit. If the bit's value is 0, the computer does not retain any magnetic charge at that place.
Data saved on a solid-state drive (SSD) or in memory operates similarly, utilizing electricity rather than magnetism. When a bit in memory holds a value of 1, a minor electrical charge alters the value at that memory location to the "on" state. If the bit value is 0, the corresponding location is designated as "off." Computers operate using binary code, represented by 0s and 1s, which differs fundamentally from human cognition. We would greatly prefer to conceptualize our data in terms of alphanumeric characters. Computers aggregate data with which we are more acquainted by amalgamating several bits. Two pieces of data can collectively represent four distinct values.
Data saved on a solid-state drive (SSD) or in memory operates similarly, utilizing electricity rather than magnetism. When a bit in memory holds a value of 1, a minor electrical charge alters the value at that memory location to the "on" state. If the bit value is 0, the corresponding location is designated as "off." Computers operate using binary code, represented by 0s and 1s, which differs fundamentally from human cognition. We would greatly prefer to conceptualize our data in terms of alphanumeric characters. Computers aggregate data with which we are more acquainted by amalgamating several bits. Two pieces of data can collectively represent four distinct values.
The 2-bit values can represent integers ranging from 0 to 3. We assign each of the 2-bit binary combinations a corresponding whole number. The table presents the standard conversion for these two-bit values.
Three bits of data can represent eight distinct values: 000, 001, 010, 011, 100, 101, 110, and 111. These translate to decimal numbers between 0 and 7.
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Chemistry - Historical models of the atom
As scientists discovered new evidence, the scientific model of the atom was updated or replaced.
1)An early model
Atoms were originally thought to be tiny spheres that could not be made smaller.
2 Plum pudding model
Electrons were discovered.
negative electron
The atom is a positively charged sphere containing electrons.
The alpha particle-scattering experiment showed that most positive alpha
particles fired at an atom went through the atom.
3)
Nuclear model
Atom’s mass is mainly a positive central nucleus
4)
Niel Bohr’s model
Bohr's calculations agreed with experiments showing the electron orbits.
small, positively charged sphere
experiment showed that the positive nucleus was made of small, positively charged particles, which were given the name 'protons'.
5)
Atomic model with protons
6)
Atomic model with neutrons
James Chadwick's experiments showed, about 20 years after the nucleus had been accepted, that the nucleus also contained particles with no charge; these were given the name neutron
As scientists discovered new evidence, the scientific model of the atom was updated or replaced.
1)An early model
Atoms were originally thought to be tiny spheres that could not be made smaller.
2 Plum pudding model
Electrons were discovered.
negative electron
The atom is a positively charged sphere containing electrons.
The alpha particle-scattering experiment showed that most positive alpha
particles fired at an atom went through the atom.
3)
Nuclear model
Atom’s mass is mainly a positive central nucleus
4)
Niel Bohr’s model
Bohr's calculations agreed with experiments showing the electron orbits.
small, positively charged sphere
experiment showed that the positive nucleus was made of small, positively charged particles, which were given the name 'protons'.
5)
Atomic model with protons
6)
Atomic model with neutrons
James Chadwick's experiments showed, about 20 years after the nucleus had been accepted, that the nucleus also contained particles with no charge; these were given the name neutron
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Computer Structure – Primary Storage Devices
Primary Storage Devices
Primary storage, also known as main memory, or internal memory, is memory that is accessed directly by the CPU.
Random Access Memory (RAM)
Computer memory is made up of silicon chips and is the computer’s working area. This is where software instructions and data are stored. This type of memory is known as volatile memory as it requires a power source to maintain the stored data. Once the power is cut, the data is lost.
Primary Storage Devices
Primary storage, also known as main memory, or internal memory, is memory that is accessed directly by the CPU.
Random Access Memory (RAM)
Computer memory is made up of silicon chips and is the computer’s working area. This is where software instructions and data are stored. This type of memory is known as volatile memory as it requires a power source to maintain the stored data. Once the power is cut, the data is lost.
For example if you are typing a document in Microsoft Word, both Microsoft Word and your document are loaded into and stored in the computer’s memory while you are working on it. This is not to be confused with the Hard Disk.
DRAM
The first type of RAM we’ll take a look at is DRAM. DRAM stands for Dynamic Random Access Memory and is the memory used to store data in
personal computers.
DRAM stores each bit of information in a cell composed of a capacitor and a transistor. The transistor admits current to the capacitor during writes, and discharges the capacitor during reads.
DRAM
The first type of RAM we’ll take a look at is DRAM. DRAM stands for Dynamic Random Access Memory and is the memory used to store data in
personal computers.
DRAM stores each bit of information in a cell composed of a capacitor and a transistor. The transistor admits current to the capacitor during writes, and discharges the capacitor during reads.
If there is a charge in the capacitor, it is read as a 1, if there is no charge, it is read as a 0.
The capacitor in a DRAM cell can hold a charge for only a few milliseconds, and is said to be ‘dynamic’, because the cell must be constantly recharged (or refreshed) in order to retain its data.
SDRAM
The next type of RAM is called SDRAM (or synchronous DRAM). This type of DRAM is called synchronous because its operation is synchronized with an external clock signal (such as the computer’s internal clock). SDRAM uses only the rising edge of the clock signal to transfer data
The capacitor in a DRAM cell can hold a charge for only a few milliseconds, and is said to be ‘dynamic’, because the cell must be constantly recharged (or refreshed) in order to retain its data.
SDRAM
The next type of RAM is called SDRAM (or synchronous DRAM). This type of DRAM is called synchronous because its operation is synchronized with an external clock signal (such as the computer’s internal clock). SDRAM uses only the rising edge of the clock signal to transfer data
DDR SDRAM
DDR stands for Double Data Rate and is a memory technology that works by allowing operations to occur on both the rising and falling edge of the clock cycle, thereby effectively doubling the data rate without increasing the clock frequency.
DDR stands for Double Data Rate and is a memory technology that works by allowing operations to occur on both the rising and falling edge of the clock cycle, thereby effectively doubling the data rate without increasing the clock frequency.
The data is stored in memory cells arranged in a grid like pattern called a memory array. The rows are called wordlines and the columns are called bitlines. Each memory array can contain thousands of cells or even millions, but to simplify the design so we can understand what’s going on, we’ll use an 8x8 memory array.
During a read cycle:
1. During a read cycle:
1. The row address is placed on the address pins via the address bus.
2. The RAS pin is activated. This places the row address into the Row Address Buffer.
3. The Row Decoder selects the row which is sent to the Sense Amp.
4. The Write Enable pin is deactivated.
5. The column address is placed on the address pins via the address bus.
6. The CAS pin is activated. This places the column address into the Column
Address Buffer.
1. The Column Decoder selects the data from the selected column in the Sense Amp, and places it on the Data Out pin, which is connected to the data bus.
2. Refresh row with data from Sense Amp.
3. The RAS and CAS pins are both deactivated and the cycle begins again.
During a write cycle:
1. The row address is placed on the address pins via the address bus.
2. The RAS pin is activated. This places the row address into the Row Address Buffer.
3. The Row Decoder selects the row which is sent to the Sense Amp.
4. The input value placed on the Data In pin, then the Write Enable pin is activated.
5. The column address is placed on the address pins via the address bus
6. The CAS pin is activated. This places the column address into the Column Address Buffer.
7. The value from the Data In pin is loaded into the Sense Amp according to
8. Refresh row (with the modified data from Sense Amp).
9. The RAS and CAS pins are both deactivated and the cycle begins again.
A single memory array would just store and retrieve one bit of data. To store a byte, we would need an 8 of these arrays
During a read cycle:
1. During a read cycle:
1. The row address is placed on the address pins via the address bus.
2. The RAS pin is activated. This places the row address into the Row Address Buffer.
3. The Row Decoder selects the row which is sent to the Sense Amp.
4. The Write Enable pin is deactivated.
5. The column address is placed on the address pins via the address bus.
6. The CAS pin is activated. This places the column address into the Column
Address Buffer.
1. The Column Decoder selects the data from the selected column in the Sense Amp, and places it on the Data Out pin, which is connected to the data bus.
2. Refresh row with data from Sense Amp.
3. The RAS and CAS pins are both deactivated and the cycle begins again.
During a write cycle:
1. The row address is placed on the address pins via the address bus.
2. The RAS pin is activated. This places the row address into the Row Address Buffer.
3. The Row Decoder selects the row which is sent to the Sense Amp.
4. The input value placed on the Data In pin, then the Write Enable pin is activated.
5. The column address is placed on the address pins via the address bus
6. The CAS pin is activated. This places the column address into the Column Address Buffer.
7. The value from the Data In pin is loaded into the Sense Amp according to
8. Refresh row (with the modified data from Sense Amp).
9. The RAS and CAS pins are both deactivated and the cycle begins again.
A single memory array would just store and retrieve one bit of data. To store a byte, we would need an 8 of these arrays
A set of memory arrays is called a bank.
On a stick of RAM, you’ll usually find 8 banks on a side. This is called a rank.
A stick of RAM is called a DIM (Dual Inline Memory Module). DDR SDRAM comes in different forms such as: DDR, DDR2, DDR3 and DDR4.
Laptops have their own type of memory. It’s more or less the same except for the physical size. These memory modules are called SO-DIMMs
On a stick of RAM, you’ll usually find 8 banks on a side. This is called a rank.
A stick of RAM is called a DIM (Dual Inline Memory Module). DDR SDRAM comes in different forms such as: DDR, DDR2, DDR3 and DDR4.
Laptops have their own type of memory. It’s more or less the same except for the physical size. These memory modules are called SO-DIMMs
SRAM
SRAM or static RAM is a lot faster than DRAM because it doesn’t need to be refreshed and is reserved for cache memory.
SRAM or static RAM is a lot faster than DRAM because it doesn’t need to be refreshed and is reserved for cache memory.
Cache Memory
The cache is usually an extremely fast memory chip that stores data so that subsequent requests for that data can be served faster.
Data read from a hard disk drive can be stored in a cache, so when a program requests that data again, it can be read from the cache instead of from the hard disk drive.
The cache is usually an extremely fast memory chip that stores data so that subsequent requests for that data can be served faster.
Data read from a hard disk drive can be stored in a cache, so when a program requests that data again, it can be read from the cache instead of from the hard disk drive.
Read Only Memory (ROM)
Read Only Memory is non-volatile memory or storage containing data that cannot be changed.
Read Only Memory is useful for storing a program that very rarely change. An example is the BIOS program needed to start a PC, sometimes known as firmware.
Read Only Memory is non-volatile memory or storage containing data that cannot be changed.
Read Only Memory is useful for storing a program that very rarely change. An example is the BIOS program needed to start a PC, sometimes known as firmware.
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Secondary Storage
Computer software and data are permanently stored in memory, which is often referred to as secondary storage or auxiliary storage. Since this kind of memory can keep its contents even when the power is switched off, it is referred to as non-volatile memory. Non-volatile memory is employed for backup and long-term storage.
A secondary storage device, such a hard disk drive, is where you store files, applications, and operating systems that you install.
There are three categories of secondary storage devices: solid state, optical, and magnetic.
Hard disk drives and other magnetic storage systems store data by magnetizing certain areas of the disk with the help of a magnetic field. These gadgets are typically inexpensive and have enormous capacities.
Flash memory is used by solid state devices to store data. These gadgets are usually quick, costly, and have little capacities.
Optical devices read data from CDs, DVDs, and Blu-ray disks using a laser. Additionally, writing data to a disk is possible, but it is typically permanent and cannot be removed.
SATA cables are typically used to connect secondary storage devices to the motherboard. The hard drive is located on the left in this image, and the SATA cable is connected to a SATA port on the motherboard.
Computer software and data are permanently stored in memory, which is often referred to as secondary storage or auxiliary storage. Since this kind of memory can keep its contents even when the power is switched off, it is referred to as non-volatile memory. Non-volatile memory is employed for backup and long-term storage.
A secondary storage device, such a hard disk drive, is where you store files, applications, and operating systems that you install.
There are three categories of secondary storage devices: solid state, optical, and magnetic.
Hard disk drives and other magnetic storage systems store data by magnetizing certain areas of the disk with the help of a magnetic field. These gadgets are typically inexpensive and have enormous capacities.
Flash memory is used by solid state devices to store data. These gadgets are usually quick, costly, and have little capacities.
Optical devices read data from CDs, DVDs, and Blu-ray disks using a laser. Additionally, writing data to a disk is possible, but it is typically permanent and cannot be removed.
SATA cables are typically used to connect secondary storage devices to the motherboard. The hard drive is located on the left in this image, and the SATA cable is connected to a SATA port on the motherboard.
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Chemistry - elements, mixtures and compounds
Substances can be (1) pure elements, (2) pure compounds or (3) mixtures of elements or compounds.
Atoms
All substances are made of atoms. An individual atom is too small to see, so everything around you contains very many atoms.
If an element is divided into smaller and smaller pieces, an atom is the smallest part that can exist.
Elements
An element is a substance that is made of only one sort of atom. Oxygen is an element because it contains only oxygen atoms.
There are about 100 different elements. Atoms of each element are given a chemical symbol.
Every symbol starts with a capital letter, often followed by a lower case letter. For example, N represents a nitrogen atom, but Na represents a sodium atom.
•The elements are shown in the periodic table.
Compounds
Compounds form when atoms of different elements are combined during a chemical reaction. Compounds can separate back into elements only through chemical reactions.
The different elements combined in a compound are in fixed proportions, shown in the chemical formula.
Example
H20
The formula of every water molecule is H20 because in each molecule two hydrogen atoms are chemically combined with one oxygen atom.
Mixtures
A mixture consists of two or more elements and/or compounds. These components are not chemically bonded. The chemical properties of each component in the mixture remain unchanged.
Worked example
Some iron powder and some sulfur powder are mixed, and tested with a magnet. The mixture is heated and cooled. The product is then tested with the magnet.
Explain why the magnet attracts some of the mixture before heating, but none of the product after heating.
(2 marks)
The magnet attracts the iron, which is magnetic.
When the mixture is heated iron sulfide is formed, which is non-magnetic.
In the mixture, iron retains its magnetic property,
Substances can be (1) pure elements, (2) pure compounds or (3) mixtures of elements or compounds.
Atoms
All substances are made of atoms. An individual atom is too small to see, so everything around you contains very many atoms.
If an element is divided into smaller and smaller pieces, an atom is the smallest part that can exist.
Elements
An element is a substance that is made of only one sort of atom. Oxygen is an element because it contains only oxygen atoms.
There are about 100 different elements. Atoms of each element are given a chemical symbol.
Every symbol starts with a capital letter, often followed by a lower case letter. For example, N represents a nitrogen atom, but Na represents a sodium atom.
•The elements are shown in the periodic table.
Compounds
Compounds form when atoms of different elements are combined during a chemical reaction. Compounds can separate back into elements only through chemical reactions.
The different elements combined in a compound are in fixed proportions, shown in the chemical formula.
Example
H20
The formula of every water molecule is H20 because in each molecule two hydrogen atoms are chemically combined with one oxygen atom.
Mixtures
A mixture consists of two or more elements and/or compounds. These components are not chemically bonded. The chemical properties of each component in the mixture remain unchanged.
Worked example
Some iron powder and some sulfur powder are mixed, and tested with a magnet. The mixture is heated and cooled. The product is then tested with the magnet.
Explain why the magnet attracts some of the mixture before heating, but none of the product after heating.
(2 marks)
The magnet attracts the iron, which is magnetic.
When the mixture is heated iron sulfide is formed, which is non-magnetic.
In the mixture, iron retains its magnetic property,
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Filtration, crystallisation and chromatography
Mixtures are separated by physical processes.
Separation of mixtures does not require chemical reaccions and no new substances are made.
Filtration
filter paper
evaporating basin
filtrate
The mixture is poured into the tunnel.
1. Insoluble solids remain in the filter paper.
2. Solutions and liquids go through into the flask.
Mixtures are separated by physical processes.
Separation of mixtures does not require chemical reaccions and no new substances are made.
Filtration
filter paper
evaporating basin
filtrate
The mixture is poured into the tunnel.
1. Insoluble solids remain in the filter paper.
2. Solutions and liquids go through into the flask.
Filtration
Crystallisation
The solution is heated to concentrate the solution, and crystals may start to form.
It is then left in a warm place for the remaining water to evaporate
Crystals form.
The solution is heated to concentrate the solution, and crystals may start to form.
It is then left in a warm place for the remaining water to evaporate
Crystals form.
Paper chromatography
To set up paper chromatography:
draw a pencil line near the bottom of the paper
add spots of colourings to the line
put the paper into a chromatography tank with
a solvent at the bottom and below the line.
The soluble dyes are carried up the chromatography paper. Different dyes travel upwards
at different rates.
To set up paper chromatography:
draw a pencil line near the bottom of the paper
add spots of colourings to the line
put the paper into a chromatography tank with
a solvent at the bottom and below the line.
The soluble dyes are carried up the chromatography paper. Different dyes travel upwards
at different rates.
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Chemistry -Distillation
Distillation is used to separate liquid from a mixture.
Simple distillation
The condenser has two tubes, one inside the other. Cold water runs through the space between the two tubes, keeping the condenser cold. The cooling water does not mix with the substance being separated.
In a mixture of two liquids, the liquid with the lower boiling point is collected as the distillate.
In a solution of a solid in water, the water is collected as the distillate.
Distillation is used to separate liquid from a mixture.
Simple distillation
The condenser has two tubes, one inside the other. Cold water runs through the space between the two tubes, keeping the condenser cold. The cooling water does not mix with the substance being separated.
In a mixture of two liquids, the liquid with the lower boiling point is collected as the distillate.
In a solution of a solid in water, the water is collected as the distillate.
Fractional Distillation
Fractional distillation is used to separate a mixture of more than two liquids using the laboratory apparatus shown.
The column is packed with glass beads. The different liquids leave the top of the column in order of increasing boiling point.
Fractional distillation is used to separate a mixture of more than two liquids using the laboratory apparatus shown.
The column is packed with glass beads. The different liquids leave the top of the column in order of increasing boiling point.
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Computer Structure - Hardware Parts
Hardware components such as a central processor unit (CPU), random-access memory (RAM), hard disk drive (HDD), and others make up computer systems. Usually connecting to a motherboard, this is referred to as internal hardware.
Peripherals are external devices such as printers, scanners, keyboards, mouse, cameras, and so on.
Additionally, there is removable storage that is meant to be portable, including memory cards, USB sticks, and external hard drives.
Hardware Types
The casing of a desktop computer contains all of the internal components. External hardware is what's located outside the case and is referred to as peripherals.
Internal Hardware
Hardware found inside the computer casing is referred to as internal hardware. Examples include the hard drive, graphics card, RAM, CPU, or processor.
External hardware / Perioherals
The most common peripherals are
Monitors Printers Keyboards Mice Scanners Cameras
These all sit outside the case and connect to your computer via USB cable or similar.
Some familiar ones are pictured below. Here, you have a computer monitor and printer. These are sometimes called output devices.
Hardware components such as a central processor unit (CPU), random-access memory (RAM), hard disk drive (HDD), and others make up computer systems. Usually connecting to a motherboard, this is referred to as internal hardware.
Peripherals are external devices such as printers, scanners, keyboards, mouse, cameras, and so on.
Additionally, there is removable storage that is meant to be portable, including memory cards, USB sticks, and external hard drives.
Hardware Types
The casing of a desktop computer contains all of the internal components. External hardware is what's located outside the case and is referred to as peripherals.
Internal Hardware
Hardware found inside the computer casing is referred to as internal hardware. Examples include the hard drive, graphics card, RAM, CPU, or processor.
External hardware / Perioherals
The most common peripherals are
Monitors Printers Keyboards Mice Scanners Cameras
These all sit outside the case and connect to your computer via USB cable or similar.
Some familiar ones are pictured below. Here, you have a computer monitor and printer. These are sometimes called output devices.
