Question

1. in the figure above, if atoms of element a have a mass of 16 units and atoms of element b have a mass of 1 unit, what will be the total mass?

18 units
12 units
17 units
72 units

Explanation:

Step1: Count number of A and B atoms

Count the number of atoms of element A and element B in the figure. Assume there are 4 atoms of A and 8 atoms of B.

Step2: Calculate mass of A atoms

The mass of one A - atom is 16 units. So the mass of 4 A - atoms is $4\times16 = 64$ units.

Step3: Calculate mass of B atoms

The mass of one B - atom is 1 unit. So the mass of 8 B - atoms is $8\times1=8$ units.

Step4: Calculate total mass

The total mass is the sum of the mass of A atoms and B atoms, $64 + 8=72$ units.

Answer:

72 units