Hitung massa molekul H2, O2, Cl2, CO2, CH4, C2H6, C2H4, NH3, CH3OH.

Penyelesaian:

Jumlah total massa atom atau unsur yang ada dalam molekul disebut massa molekul.

  1. i) Massa molekul H 2 = 2 x Massa atom H

= 2×1

Massa molekul H 2 = 2 u

  1. ii) massa molekul O 2 = 2 x Atom massa O

= 2 x 16

Massa molekul O 2 = 32 u

iii) Massa molekul Cl 2 = 2 x Massa atom Cl

= 2 x 35,5

Massa molekul Cl 2 = 71 u

  1. iv) Massa molekul CO 2 = Massa atom C + 2 x Massa atom O

= 12 + 2 x 16

Massa molekul CO 2 = 44 u

  1. v) Massa molekul CH 4 = Massa atom C + 4 x Massa atom H

= 12 + 4 x 1

Massa molekul CH 4 = 16 u

  1. vi) Massa molekul C 2 H 6 = 2 x Massa atom C + 6 x Massa atom H

= 2 x 12 + 6 x 1

Massa molekul C 2 H 6 = 30 u

vii) Massa molekul C 2 H 4 = 2 x Massa atom C + 4 x Massa atom H

= 2 x 12 + 4 x 1

Massa molekul C 2 H 4 = 28 u

viii) Massa molekul NH 3 = Massa atom N + 3 x Massa atom H

= 14 + 3 x 1

Massa molekul NH 3 = 17 u

  1. ix) Massa molekul CH 3 OH = Massa atom C + 4 x Massa atom H + 1 x Massa atom

= 12 + 4 x 1 + 16

Massa molekul CH 3 OH = 32 u

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March 29, 2022 10:28 pm