If an atom has an atomic number of 12 and a mass number of 16 how many protons does it have

Both 1,2−dihydronaphthalene and 1,4−dihydronaphthalene may be selectively hydrogenated to 1,2,3,4−tetrahydronaphthalene. one of these isomers has a heat of hydrogenation of 101 kj/mol (24.1 kcal/mol), and the heat of hydrogenation of the other is 113 kj/mol (27.1 kcal/mol). match the heat of hydrogenation with the appropriate dihydronaphthalene.

This image is an example of a(n) a) atom. b) compound. c) mixture. d) molecule.

In a reaction (at equilibrium) that makes more moles of gas than it consumes, what is the effect of increasing the pressure?