Skip to content

Course home

3.2 Use of amount of substance in relation to masses of pure substances

3.2 Use of amount of substance in relation to masses of pure substances

EasyMediumHard
12345678910111213141516171819202122232425262728
Question 24

Silane, SiH4\text{SiH}_4SiH4​, is a gas that reacts with oxygen to produce solid silicon dioxide and water vapour.

The equation for the reaction is:

SiH4(g)+2O2(g)→SiO2(s)+2H2O(g) \text{SiH}_4(\text{g}) + 2\text{O}_2(\text{g}) \rightarrow \text{SiO}_2(\text{s}) + 2\text{H}_2\text{O}(\text{g}) SiH4​(g)+2O2​(g)→SiO2​(s)+2H2​O(g)

50 cm350\text{ cm}^350 cm3 of SiH4\text{SiH}_4SiH4​ is reacted with 140 cm3140\text{ cm}^3140 cm3 (an excess) of oxygen.

Calculate the total volume of gases present after the reaction is complete.

All volumes of gases are measured at the same temperature and pressure. Assume the temperature is high enough that water remains in the gas phase.

[4]
Markscheme

3.2 Use of amount of substance in relation to masses of pure substances Questions

  1. GCSE
  2. /Chemistry
  3. /3.2 Use of amount of substance in relation to masses of pure substances

38 exam-style questions on AQA GCSE Chemistry 3.2 Use of amount of substance in relation to masses of pure substances, covering 3.2.1 Moles (HT only), 3.2.2 Amounts of substances in equations (HT only), 3.2.3 Using moles to balance equations (HT only), 3.2.4 Limiting reactants (HT only), and 3.2.5 Concentration of solutions. Each one has a worked solution and a mark scheme showing where the marks go.

Question bank