AQA Chemistry GCSE C1 Higher - Unofficial Mark Scheme Period.

If anyone is interested, my predictions for the grade boundaries are: A*- 50, A-41, B-33 C-25

It is wrong?

If I got a high A (coursework), a high B, and two low B's, would this be a B overall? (i do core science)

yep, deifinitely a b

I think that's too high. A couple of years ago 39 was an A*, I think something like 47 will be an A*

thank you! i put 41 then crossed it out so hopefully i havent lost the mark!

Atomic structure

What is atomic number? (1 mark)

The number of protons.

What is atomic mass? (1 mark)

Number of protons and neutrons.

Why is there no overall charge? (2 marks)

Same number of protons and electrons, balancing the charges.

Why is Chlorine and Fluorine in the same group? (2 marks)

Because they both have 7 electrons in the outer shell.

Identify the element (1 mark)

Sulphur.

Metal and non metals reacting would form particles called ions (1 mark)
Non metals reacting would form particles called molecules. (1 mark)

Limestone question

Thermal decomposition. (1 mark)
Alkali. (1 mark)
Water. (1 mark)
Carbonate (1 mark).

Mortar&Aggregate

Draw 2 lines of best fit. (2 marks)

Describe one way how they could improve the accuracy of the test? (2 mark)

Repeating the test, to calculate a mean. Improving accuracy of points on the graph.

Force required for 0 grams of aggregate (2 marks)

Had to extend the line of best fit to 0, which is 44 newtons.

Why is his conclusion wrong? (3 marks)

Because the force did increase up until reaching 400 grams of aggregate, however after 400 grams of aggregate used the force decreased with the mass of 500, 600, 700.

Atmosphere

Explain why there are many theories involving how simple life were formed? (1 mark)

Because there's no conclusive evidence supporting one theory.

6 marker on the atmosphere

-Volcanic activity released carbon dioxide and also water vapour in the air, increasing levels of both in the early atmosphere.
-Earth cooled, decreasing levels of water vapour, and forming oceans.
-Carbon dioxide dissolves in the oceans, decreasing levels of carbon dioxide.
-Plant life do photosynthesis decreasing levels of carbon dioxide in the air and also increase levels of oxygen.

Metals and their uses

Why do we need to do stage 1 which is separation ? (2 marks)

Because separation of the ore, means that the ore would now be more concentrated of that metal and therefore allowing it to be more economical.

Why is cast iron not used for over head cables? (1 mark)

Can rust easily.

How is cast iron formed? (2 marks)

Carbon is removed from molten iron by blowing oxygen into it. The oxygen reacts with the carbon, producing carbon monoxide and carbon dioxide, which escape from the molten metal. Enough oxygen is used to achieve steel with the desired carbon content.

Property of Aluminium (1 mark)

Low density

Transition metals and how can you tell copper is a transitional metal and not Aluminium. (3 marks?)

Aluminium is in group 3, and group 3 metals are not transitional metals. Copper is in the middle section of the periodic table where transitional metals are located.

Crude oil

Fractioning columns ( 4 marks)

Crude oil has a mixture of hydrocarbons.
Crude oil is vaporised.
Crude oil is condensed.
At different boiling points and collected.

Why is limestone suspension used and which environmental factor does it decrease? (3 marks)

Sulphur dioxide forming sulphuric acid reacting with the limestone as a neutralisation reaction, decreasing levels of sulphur dioxide in the air which as a result less acid rain.

Finish cracking (1 mark)
C₂H₄

Polymerisation drawing (3 marks)

Removal of double bond.
Adding a bond on the brackets. -()-

Smart polymer property (1 mark)

Shape memory.

Vegetable oils

Weird question poorly worded, since it was in reference for food and fuel.

Why are vegetable oils important? (1 mark)

Provide high energy.

2 main stages (2 marks)

-Crushed
-Oil removed by pressing or distillation.

One use of vegetable oil over than using water for cooking? (2 marks)

-Vegetable oil has a higher boiling point than water, this means that the food will be cooked at high temperatures so making it quicker.
-Different tastes
-Wider variety of flavours.

Emulsifier (4 marks)

-Hydrophilic head is attached to the water.
-Hydrophobic tail is attached to the oil.
-Stops separation of both liquids.

Full paper is here, surprised myself with the memory that was put into this. Be sure to rep this post. Hope you've done well, cheers <3.

I think that's too high. A couple of years ago 39 was an A*, I think something like 47 will be an A*

That's if it was calcium hydroxide, but it wasn't. It was calcium carbonate.

Vegetable oils

Weird question poorly worded, since it was in reference for food and fuel.

Why are vegetable oils important? (1 mark)

Provide high energy.

Did the question say Limestone rather than Limewater? I must've misread it.

What was force required to break the thing coz the unofficial mark scheme is wrong I think