If an element has an atomic number of 12 how many protons does each atom have?

Melting and boiling are endothermic processes. this means that these processes absorb energy from their surroundings in order to occur. use this information and the data you collected in the phase change gizmo to describe what happens to the temperature of water when you boil it, then explain why this result occurs.

If 90.0 grams of ethane reacted with excess chlorine, how many grams of dicarbon hexachloride would form

How many grams of oxygen gas are contained in a 15 l sample at 1.02 atm and 28°c? show your work.