GCSE COMBINED SCIENCE HIGHER: CHEMISTRY 2018 PAPER 1

Notes:

Question 1.1 chlorine

1.2 copper is less reactive than hydrogen

1.3) 0.6 + 1.2 + 2.4 + 3.06 = 7.26

1.4 watch a yt on to how to answer that question

7.26 / 4 = 1.815

 answer = 1.8mg

1.5

0.05 x 300 = 15g still watch a yt video for that question

2.2 sodium loses one electron. sodium now has a negative ion. chlorine gains one electron. chlorine now has a positive ion

2.3 watch a yt video for that question

2.1 difference = sodium has 1 electron in their outer shell, chlorine has seven electrons in its outer shell 

similarity = they both have incomplete outer shells

Question 3)

The student should use sulphuric acid as this will make sulphate instead of the hydrochloric acid which makes chlorides.

they should make copper carbonate instead.

The student should add carbonate until no more reacts. they should then filter this to remove the excess solid.

They should finally, heat gently until nearly evaporated and left to slowly crystallise. 

 

Question 4.1  g (make sure it is lower case g)

4.2  watch a yt to answer that question

4.3 18

4.4  2AI + 3Br2 ---> 2AIBr3

4.5 Chlorine is more reactive than bromine because it is more reactive in group 7 which means it has fewer energy levels so therefore chlorine can gain an electron more easily.

5.1 Diamond had a low melting point because

• each carbon atom is joined to four other carbon atoms by covalent bonds
•  a large amount of energy is needed to overcome the many strong covalent bonds.
• it has a giant covalent structure 

5.2 If you dissolve sodium chloride in water, the ionic lattice breaks apart and the sodium and chloride ions are free to move around.

5.3 watch a YT video

Question 6.1  CaO and CO2

6.2  12 + (3 x 16) = 60

197 - 60 = 137 

relative atomic mass = 137

metal = barium

6.3  watch a yt video

6.4  

8.1 hydrogen

8.2 filtration

8.3 

8.4 iron is being reduced (Fe 3+)

Fe 3+   +  3e(-)  --->  Fe

reduction is the gain of electrons

 

 

 

 

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