[急!!!!!]F.1 Science 問題(10點)

First of all, I have to tell you that my answer may not be suitable for you as you may not have learned what I am going to type below. I will try to make it simple.
i) The mass of solid X would not change as the solid X still contains the same number of particles/nucleons after being heated.
ii) The volume of solid X would increase when heated. This is called thermal expansion. When solid X is heated, the particles in the solid gain more kinetic energy and hence the particles oscillate about their equilibrium position more vigorously. This increases the mean separation between each particle, so the solid expand.
iii) m=pV m=mass, p=density, V=volume
As stated above, the mass of solid(m) remains unchanged while the volume(V) increases, so the density of the solid(p) decreases.
Hope that my answer help.

太耐冇理,,變左投票⊙_⊙......
不過我投你就得啦