Molar mass
Please give me the answers and explain

Explanation:

The molar mass of a substance is the mass in grams of one mole of the substance. In a compound, add the atomic masses of the components.

 HCl

 Atomic mass of H  = 1g/mol,  Cl = 35.5g/mol

   HCl  = (1 + 35.5) = 36.5g/mol

 ZnF₂

Atomic mass of Zn  = 65.4g/mol, F = 19g/mol

      ZnF₂  = 65.4 + 2(19) = 103.4g/mol

 K₂CO₃

   Atomic mass of K = 39, C  = 12, O = 16

    K₂CO₃  = 2(39) + 12 + 3(16)  = 138g/mol

 FePO₄

Atomic mass of Fe = 55.8, P = 31, 0 = 16

 FePO₄ = 55.8 + 31 + 4(16) = 150.8g/mol

Cu₂S

  Atomic mass of Cu = 63.5g/mol, S = 32

    Cu₂S = 2(63.5) + 32 = 159g/mol

the answer is a! (2.9 x 10^-18 j) hope i could someone. : )