Is browning and producing new flavor compounds as something cooks a chemical or a physical change?

This chart represents the melting point of several substance. what besy explains the high melting point of the salt?

Iwill give extra points to who gets this right

In the 1800s, one of the statements in john dalton's atomic theory was that atoms are indivisible. later experimental evidence led to the discovery of subatomic particles such as neutrons, electrons, and protons. what happened to the indivisible atom part of dalton's atomic theory, and why?