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

answers: to make sure that all of the broken pieces of tablet were added to the water, to allow for fair comparison of all three trials, with different particle sizes to avoid experimental error