STPM Chemistry Questions

Monoxides and dioxides of Group 14 elements in the Periodic Table show different acid-base properties. Which is an acidic oxide?

• GeO

• PbO

• SiO₂

• SnO₂

Which ionic compound is stable due to the inert pair effect?

• GeO

• PbO₂

• PbCl₂

• GeCl₄

Which oxide of Group 14 would bleach the colour of a damp litmus paper when reacting with hot concentrated hydrochloric acid?

• CO₂

• PbO

• CO

• PbO₂

Which statement is true of the oxides of Group 14 elements in the Periodic table on descending the group?

• The thermal stability of the dioxides of the elements increases.

• The stability of the +2 oxidation state of the elements decreases.

• The ionic properties of the monoxides of the elements increase.

• The acid-base properties of the dioxides of the elements change from acidic to basic.

Which is a common property for germanium and lead compounds?

• Stability of +2 oxidation state of both compounds is due to the inert pair effect.

• Tetrachlorides of both compounds are thermally stable.

• Dioxides of both compounds are amphoteric.

• Monoxides of both compounds are basic.

A thermally stable liquid, MCl₄, reacts with water to form a solution of low pH value. Which statement about M or its oxides is true?

• MO is an acidic oxide.

• MO exists as simple molecules.

• MO is a reducing agent.

• M is a good electrical conductor