Chemistry 5070 · O Level · Elements, compounds and mixtures
Elements, compounds and mixtures — practice question
Select your answers from the gases listed below.
ammonia
argon
carbon dioxide
chlorine
ethane
ethene
nitrogen
nitrogen(II) oxide
oxygen
sulfur dioxide
Each gas may be used once, more than once, or not used at all.
(a)[1]
Which gas makes up approximately 1% of air?
(b)[1]
Which gas bleaches damp litmus paper?
(c)[1]
Which gas reacts with water to form an alkaline solution?
(d)[1]
Which gas can undergo polymerisation?
(e)[1]
Which gas is a compound formed in the atmosphere as a result of lightning activity?
(f)[1]
Which gas is a diatomic molecule containing a total of 16 electrons?
Worked solution & mark scheme
This 6-mark question has a full step-by-step worked solution and mark scheme. One marking point: “Ar” …