BGCSE Chemical Composition and Reactions

Front

What is the balanced equation for the reaction between hydrogen and chlorine gas?

Back

H₂(g) + Cl₂(g) → 2HCl(g)

Front

How do you calculate the volume of gas produced in a reaction at room temperature and pressure (r.t.p.)?

Back

Use the molar volume of gas at r.t.p., which is 24 L/mol, and the stoichiometry of the balanced equation.

Front

What is the oxidation number of oxygen in hydrogen peroxide (H₂O₂)?

Back

-1

Front

What is the process called when a substance gains electrons?

Back

Reduction

Front

What is the function of carbon in the reaction 2CuO + C → 2Cu + CO₂?

Back

Carbon acts as a reducing agent.

Front

What is the relative formula mass of H₂SO₄?

Back

98 g/mol

Front

Define a reducing agent in a chemical reaction.

Back

A reducing agent is a substance that donates electrons to another substance, causing the other substance to be reduced.

Front

What is the difference between oxidation and reduction?

Back

Oxidation is the loss of electrons, while reduction is the gain of electrons.

Front

What is the significance of the coefficients in a balanced chemical equation?

Back

Coefficients indicate the relative amounts of reactants and products involved in the reaction.

Front

What is the molar volume of a gas at room temperature and pressure (r.t.p.)?

Back

24 L/mol.