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Chemistry GCSE C2 + C3 Game

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C2 - Why do different compounds separate in a gas chromatography column

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Reply 1
Original post by WillsWheels
Let Ask Questions!

C2 - Why do different compounds separate in a gas chromatography column


Different substances carried by the gas travel at different speeds.

C3- How do you test for carbonates?
Can someone tell me how paper chromotography works in as much detail as required for the exam please?
limewater
if carbonate ions are prescent solution goes cloudy
Original post by Londonsfalling
Can someone tell me how paper chromotography works in as much detail as required for the exam please?


ummm i'll have a go!

Chromotography is when you separate artificial colours, a lot of the time it is used to see what is in food colouring.
You put an extract of a colour from a food sample and put that in a beaker/cup, then add a few drops of solvent to it (water, salt water etc...)
Then you put spots of the solution you just made, on a piece of paper, on a pencil baseline.
Roll the paper up and put that in a beaker with water.
The solvent leaks in the paper and takes the dyes with it, separating them and forming spots showing the minimum number of dyes that are inside that sample of food!

Hope that makes sense!!!
Reply 5
Original post by Londonsfalling
Can someone tell me how paper chromotography works in as much detail as required for the exam please?


You place a pencil mark along a piece of paper and this is where you add a drop of the mixture you will be testing. This paper is placed in a beaker of solvent such as water (filled to just below your pencil line). As the solvent is soaked up, it takes the colouring's or dyes with it. Different substances will go further up the paper as they all travel at different speeds. Remember that we never use pen to draw the line as it will smudge and distort the results. I hope this helped, and good luck tomorrow!

Next Question is C2 - What is an endothermic reaction?
Reply 6
Original post by WillsWheels
You place a pencil mark along a piece of paper and this is where you add a drop of the mixture you will be testing. This paper is placed in a beaker of solvent such as water (filled to just below your pencil line). As the solvent is soaked up, it takes the colouring's or dyes with it. Different substances will go further up the paper as they all travel at different speeds. Remember that we never use pen to draw the line as it will smudge and distort the results. I hope this helped, and good luck tomorrow!

Next Question is C2 - What is an endothermic reaction?


more energy required to break boinds than to form bonds (c3 def)
Reply 7
Original post by WillsWheels
Let Ask Questions!

C2 - Why do different compounds separate in a gas chromatography column


No idea and can you explain the process
Reply 8
they travel at different speeds
why are esters used
Reply 9
Original post by aj345
they travel at different speeds
why are esters used


they are used to give a fruity taste and solvents
Original post by WillsWheels
You place a pencil mark along a piece of paper and this is where you add a drop of the mixture you will be testing. This paper is placed in a beaker of solvent such as water (filled to just below your pencil line). As the solvent is soaked up, it takes the colouring's or dyes with it. Different substances will go further up the paper as they all travel at different speeds. Remember that we never use pen to draw the line as it will smudge and distort the results. I hope this helped, and good luck tomorrow!

Next Question is C2 - What is an endothermic reaction?


A reaction which takes in energy from the surroundings

C3 - Describe and explain the reactivity of the alkali metals (4 marks)


Posted from TSR Mobile
Reply 11
as you go down the group they become more reactive as they have more shells and are further away from the nucleus so are less attracted so it is easier to lose an electron
Original post by Mahrez
No idea and can you explain the process


In gas chromatography, the mixture you will be testing is placed at the end of the column. This is carried along the column until it gets to the receiver. at this point a computer will measure the amount of time that substance has taken to reach the end of the tunnel. The mixture has separated as each substance travels at a different speed along the column. This can eventually be plotted onto a chromotagraph. I hope this helps :smile: Good Luck tomorrow!
Reply 13
why are transition metals used as water pipes
Original post by lilacpotato
A reaction which takes in energy from the surroundings

C3 - Describe and explain the reactivity of the alkali metals (4 marks)


Posted from TSR Mobile


The negative electrons are attracted to the positive nucleus. as you go down the group the number of shells increases, increasing the distance between the two so reducing the forces of attraction between them and increasing the quantity of shieling so the electron is more easily lost

C3 what happens when you react an alkali metal and water?
Reply 15
Original post by aj345
as you go down the group they become more reactive as they have more shells and are further away from the nucleus so are less attracted so it is easier to lose an electron


there is also more shielding
Original post by aj345
why are transition metals used as water pipes


1.The are strong
2. They are unreactive

C3 What is meant by a weak metal?
Copper is used as water pipes because it is strong, bendable and also doesn't corrode when it reacts with water.
Reply 18
Original post by ProbablyJade
The negative electrons are attracted to the positive nucleus. as you go down the group the number of shells increases, increasing the distance between the two so reducing the forces of attraction between them and increasing the quantity of shieling so the electron is more easily lost

C3 what happens when you react an alkali metal and water?

it forms (sodium) hydroxide and hydrogen
Reply 19
ways to remove hardness in water

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