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Higher chemitry

26. In which of the following reactions would
the products have a lower volume than the
reactants?
A 2C(s) + O2(g) → 2CO(g)
B C(s) + O2(g) → CO2(g)
C CaCO3(s) + 2HCl(aq)
→ CaCl2(aq) + CO2(g) + H2O(ℓ)
D Ca(OH)2(aq) + 2CO2(g)
→ Ca(HCO3)2(aq)

Reply 1

pwk123

Think about the states of matter of the reactants and products
Which state of matter is most dense (so takes up the least volume) and which is least dense?

Reply 2

Florie Mitchell

Original post by pwk123

Think about the states of matter of the reactants and products
Which state of matter is most dense (so takes up the least volume) and which is least dense?

So A?

Reply 3

Florie Mitchell

Original post by Florie Mitchell

So A?

Oh wait no it would be D

Reply 4

pwk123

Original post by Florie Mitchell

Oh wait no it would be D

What's your reasoning?

Spoiler

(edited 3 years ago)

Reply 5

Florie Mitchell

Is it because gas is the least dense state of matter meaning that it takes up the most volume. And D is the only answer which doesn't have a gaseous product, meaning the reactant therefore take up more volume?