What apparatus is used for preparing a standard solution, and what properties make a compound suitable for a primary standard? List apparatus for specific lab tasks.

a) To prepare 250 cm³ of 0.1 mol dm⁻³ sodium trioxocarbonate(IV) solution, the following apparatus could be used:

• Volumetric flask (250 cm³)
• Electronic balance
• Beaker
• Funnel

b) Two properties a compound must have to be suitable for the preparation of a primary standard solution are:

• It must be of high purity.
• It must be stable (not decompose, react with air, or absorb moisture/CO₂).

c) The laboratory apparatus for each task is:

i) Intermittent generation of a gas: Kipp's apparatus

ii) Keep substances dry: Desiccator

iii) Convert lumps of a salt into powder: Mortar and pestle

iv) Channeling liquids into a container with a narrow opening: Funnel