Is Dissolving of salt in water a physical or chemical change

Layers of rock containing fossils, like the layers illustrated here, are most likely composed of rocks.

When 225mg of anthracene, c14h10(s), was burned in a bomb calorimeter the temperature rose by 1.75k. calculate the calorimeter constant. by how much will the temperature rise when 125mg of phenol, c6h5oh(s), is burned in the calorimeter under the same conditions? (δch< (c14h10,s)=–7061 kj mol−1.)

What is the atomic number of an atom that has 6 protons