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AQA Chemistry Unit 2 & 3 Question Game 14th June 2016

This is the official thread for the Unit 2 & 3 question game for chemistry. Answer the question from the post above and ask another question for the next person to answer.

I'll start: --->Describe how the structure of an alloy is different from the structure of a pure metal (2 marks) <---

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Reply 1

Wikia

- Layers in alloys do not slide over eachother as the atoms are different sizes (whereas in a pure metal they do), and as a result they cannot be bent into shape.

--> What is meant by an endothermic reaction (1 mark)

Reply 2

Anmol_.

Endothermic reaction is one which absorbs energy from the surroundings in the form of heat and is seen by a fall in temperature.

Explain the process of electroplating (3 marks)

Reply 3

nerdyminion

Original post by Anmol_.

Endothermic reaction is one which absorbs energy from the surroundings in the form of heat and is seen by a fall in temperature.

Explain the process of electroplating (3 marks)

The object which is going to be electroplated is the cathode; the material that the object is going to be plated with is the anode. At the anode, the material is oxidised, meaning that it loses electrons and positively charged ions enter the solution (electrolyte). At the cathode, the positively charged ions are reduced, meaning they gain electrons and become atoms of the material.

C3: Describe the Haber process and its conditions.

Reply 4

Mahrez

Original post by nerdyminion

Temp of 450 and pressure of 200. High temp increases rate of reaction but low temp favours exo thermic side of the reaction. Increased pressure increases rate and yield but expenisve. so a comprimise is used. Sorry for dogy typing cba to explain fully :smile:

Reply 5

alchima

Original post by nerdyminion

The Haber process is the production of ammonia from nitrogen and hydrogen. The reaction is reversible and takes place in a chamber where the gases are compressed to 200atm and the temperature is 450 degrees. The unreacted nitrogen and hydrogen and ammonia will leave the chamber and is cooled. Ammonia liquefies and is tapped off and the remaining gases are recycled to make more ammonia.
Question: Give one similarity and one difference between alkali metals and halogens.

Reply 6

xxxtentacion..

Original post by alchima

Theyre both highly reactive. However, alkali metals need to lose one electron and halogens need to gain one electron.

---> How does temperature have an effect of equilibrium? <-----

Reply 7

jazz_xox_

Original post by hafsa473

Theyre both highly reactive. However, alkali metals need to lose one electron and halogens need to gain one electron.

---> How does temperature have an effect of equilibrium? <-----

A higher temperature would favour the reaction in the endothermic way to supply the heat energy needed, but in the Haber Process, more heat is compensated to increase the rate of reaction :smile:

explain the method of titration calculations

Reply 8

bborn12

does anyone know the time of the unit 2 exam tomorrow ? my schools messed up the time

Reply 9

syeds

Original post by bborn12

does anyone know the time of the unit 2 exam tomorrow ? my schools messed up the time

mine is 1:25

Reply 10

bborn12

Original post by syeds

mine is 1:25

Thank you so much

Reply 11

jazz_xox_

Original post by bborn12

does anyone know the time of the unit 2 exam tomorrow ? my schools messed up the time

Mine is 1pm- its definitely an afternoon exam depending when your school do them

Reply 12

Hassan M

Name the products of sodium chloride solution in electrolysis?

Reply 13

pratical1

A hydrogen gas
A chlorine gas
A solution of sodium hydroxide is formed.

What are the characteristics of a simple molecule structure (covalent bonding) - 3marks