The formulae below are provided.
CaCO$_3$
CaO
Cl$_2$
CH$_4$
C$_2$H$_5$OH
C$_2$H$_6$
CuSO$_4$
H$_2$
H$_2$O
MgO
NaCl
SO$_2$
Use these formulae to answer the questions that follow.
Each formula can be chosen once, more than once, or not used at all.
State which formula stands for:
(a(i))[1]
a compound that makes up the main part of natural gas
(a(ii))[1]
an element used for treating water
(a(iii))[1]
an element that turns damp litmus paper white
(a(iv))[1]
a compound that includes an ion with a single negative charge
(a(v))[1]
a hydrocarbon formed when vegetation decomposes
(b)[2]
Complete the dot-and-cross diagram for a water molecule.
(c)[1]
State whether calcium oxide is a basic oxide or an acidic oxide. Explain the reason for your answer.
Worked solution & mark scheme
This 8-mark question has a full step-by-step worked solution and mark scheme. One marking point: “CH₄ (methane)” …