How much heat has been lost when 78g piece of copper is placed into a calorimeter and cools from 120 to 40c

The difference between the atomic number of an element and the element’s atomic mass is the number of ions.

Agas diffuses 1/7 times faster than hydrogen gas (h2). what is the molar mass of the gas? 100.10 g/mol 98.78 g/mol 86.68 g/mol 79.98 g/mol

Chlorophyll a had the molecular formula c55h72mgn4o5 how many atoms are in this molecule