Explain why heating of ammonium chloride can be said both a physical and a chemical change. Give one more example.

Choose the correct type of chemical reactions (Combination reaction/ decomposition reaction/ displacement reaction).

$2\mathrm{CO} + {\mathrm{O}}_2 \to 2{\mathrm{CO}}_2$

Choose the correct type of chemical reactions (Combination reaction/ decomposition reaction/ displacement reaction).

$\mathrm{C} + {\mathrm{O}}_2 \to {\mathrm{CO}}_2$

Choose the correct type of chemical reactions (Combination reaction/ decomposition reaction/ displacement reaction).

$2{\mathrm{Pb}}_3{\mathrm{O}}_4 \stackrel{∆}{\to } 6\mathrm{PbO} + {\mathrm{O}}_2$