Question

Calculate Formula unit mass of the following-: K2CO3 2. ZnO 3. CH3OH 4. Cl2 5. CaCl2 6. HNO3​

Answer 1

K2CO3 :

Atomic weight of K ( potassium ) = 39

Atomic weight of C ( Carbon ) = 12

Atomic weight of O ( oxygen ) = 16

Molecular wright of K2CO3 = 2(39) + 12 + 3(16) = 78 + 12 + 48 = 138 amu.

ZnO :

Atomic weight of Zn = 65.3

Atomic weight of O = 16

Molecular weight of ZnO = 65.3 + 16 = 81.3 amu.

CH3OH :

Atomic weight of C = 12

Atomic weight of H = 1

Atomic weight of O = 16.

Molecular weight of CH3OH = 12 + 3(1) + 16 + 1 = 12 + 3 + 16 + 1 = 32 amu.

Cl2 :

Atomic weight of Cl = 35.5

Molecular weight of Cl2 = 2(35.5) = 71 amu.

CaCl2 :

Atomic weight of Ca = 40

Atomic weight of Cl = 35.5

Molecular weight of CaCl2 = 40 + 2(35.5) = 40 + 71 = 111 amu.

HNO3 :

Atomic weight of H = 1

Atomic weight of N = 14

Atomic weight of O = 16

Molecular weight of HNO3 = 1 + 14 + 3(16) = 1 + 14 + 48 = 63 amu.