Explain how the electrons density shift resulting from changing relative position of atoms contributes to holding the atoms together

In the particles are arranged in a regular, repeating pattern. a)a crystalline liquid b)a crystalline solid c)all gases d)all solids

A155.0 9 piece of copper at 182 °c is dropped into 2500 g of water at 23.9 °c. (the specific heat of copper is 0.385 1/9°c.) calculate the final temperature of the mixture. (assume no heat loss to the surroundings.)

The two isotopes of chlorine are 3517cl and 3717cl. which isotope is the most abundant?