When using a manometer to check boyle's law, why is the pressure changed slowly? to avoid compressing the liquid to avoid compressing the gas to avoid changing the gas temperature to avoid changing the mass of the g?

Boyle's Law is a special equation depicting ideal gas behavior. It is applicable to systems working at constant temperature, such that there is a constant for every product of pressure and volume.

PV = k

The reason why pressure is changed slowly is because pressure affects kinetic energy which defines temperature. Thus, changing the pressure slowly would help keep the temperature constant as possible. So, the answer is avoid changing the gas temperature.

1.from liquid state to gaseous state is evaporation 3.solid to liquid is melting 5. solid to gaseous state is sublimation 6. gas to solid state is decomposition 7. a change of state is known as the states of matters