## Chemistry 10th Edition

(a) Sugar does not change in composition when dissolves in water. (Physical) (b) Boiling point is a physical property. (c) Changes in composition (From $O_3$ to $O_2$). (Chemical) (d) Density is a physical property. (e) When sodium metal reacts with water, the following reaction happens: $$Na_{(s)} + H_2O_{(l)} \longrightarrow NaOH_{(aq)} + \frac 12{H_{2}}_{(g)}$$ Therefore, there is a composition change. (Chemical) (f) Combustion consists of a reaction with changes in compositions. (Chemical) (g) Melting point is a physical property.