1. What is responsible for the different phases of matter? 2. What is the temperature at which a substance changes from a liquid to a solid?
3. What is the phase change from a gas to a liquid?
4. What is the phase change from a solid directly to a gas?

1. The five phases of matter. There are four natural states of matter: Solids, liquids, gases and plasma. The fifth state is the man-made Bose-Einstein condensates. In a solid, particles are packed tightly together so they don't move much.

2. The temperature at which a substance changes from the liq- uid state to the solid state is called the freezing point. The freez- ing point of the liquid state of a substance is the same temperature as the melting point of the solid state. For example, solid water melts at 0°C and liquid water freezes at 0°C.

3. The process of a liquid becoming a gas is called boiling (or vapourization), while the process of a gas becoming a liquid is called condensation. 4. Sublimation is the process of transformation directly from the solid phase to the gaseous phase, without passing through an intermediate liquid phase.

Explanation:

hi

t2 equal the displacement of the particle over the same time period if t2> t/2? hint: consider a sine wave starting at t1=0, then consider a closing wave starting at t1=0, for your explanatio

current flows in a wire