Can somebody help me with this it is a science question part #2 ( can you also check my other questions to see if you can answer them).

The drawing represents the movement of particles in a substance. what changes of state can this substance undergo

Write the formula for the following chemicals. 7. e. trinitrogen tetraoxide a calcium phosphate f. magnesium acetate b. potassium sulfide g nickel(iii) cyanide c carbon dioxide h. silver sulfate d. cobalt(ii) chloride

Light waves can move through , but they travel fastest when they move through a(n) .