(a(i))[2]
Calculate the relative formula mass of sodium carbonate, Na$_2$CO$_3$. Show all of your working. Use your Periodic Table to help you.
(a(ii))[1]
What does the term endothermic mean?
(a(iii))[1]
What kind of chemical reaction happens when lime reacts with acidic soils? Circle the correct answer. addition, neutralisation, oxidation, reduction.
(b(i))[1]
Which gas makes up 21% of clean, dry air?
(b(ii))[1]
Write a word equation for carbon burning in excess air.
(b(iii))[1]
Complete the energy level diagram for this reaction by adding these two words: reactants, product.
(c(i))[1]
Give one use of argon.
(c(ii))[2]
Which two statements about argon are correct? Tick two boxes. Argon is unreactive. Argon is diatomic. Argon is monatomic. Argon forms ionic compounds. Argon is a greenhouse gas.