On a temperature versus time graph, how does the temperature at the beginning of a change of state compare with the temperature at the end of the change?

It Remains Constant

Explanation:

When the temperature over a matter remains constant, subsequently the kinetic energy among them is also constant, then there is a phase change.

The graph is a linear function given by the formula, which measures the heat necessary in the system:

Q=mcΔt

So it increases linearly in the same state. Remains constant when there's a change of state. According to the function above and the graph below.

answer: the rate of diffusion increases with increase in temperature.

increase in temperature, increases the molecular/particles speed (kinetic energy. diffusion means movement of particles through the material.

generally, the heavier the particle the more it interacts with the environment and more the temperature matters. so higher temperature results in higher diffusion.