Answer:

Explanation:
Hello,
In this case, the molar enthalpy of reaction is obtained by dividing the involved energy by the reacting moles:

Thus, it is important to notice that the compound "uses" the energy, it means that it absorbs the energy, for that reason the sign is positive. Moreover, computing the result in kJ/mol we finally obtain:

Best regards.
As far as I know, the answer is B (breaking a rock)
Answer:
0.779 moles.
Explanation:
Mass of chlorine/number of moles = molar mass of chlorine.
Molar mass of chlorine = (35.5*2)
= 71 g/mol.
Mass = 55.3 g of chlorine.
Number of moles = 55.3/71
= 0.779 moles.
Answer would be c hope this helped
Answer:
B. electrons and protons.
Explanation:
In an electrically neutral atom of any element, there are equal number of protons and electrons in the atom.
Protons are the positively charged particles in an atom.
Electrons are the negatively charged particles within the atom.
When the number of protons and electrons are the same or equal, the atom is neutral.
But when there is an imbalance, an ion results.