How many atoms are in 0.000045 grams of carbon?

2.25E18

Explanation:

0.000045 g of Carbon x (1 mol C/ 12.01 g C) x (6.02 x 10E23 atoms / 1 mol C)

Start with the mass, then multiply it by the molar mass but put moles on the top and grams on the bottom to cancel out the grams. Then multiply it by Avogadros Constant to get atoms

the potential energy of the reactants is 200j.

from the energy diagram, the energy of the product formed is 350j; this means that, this reaction is an endothermic reaction, because it absorbs energy from its environment.

the product of the pressure and volume is also constant