This is a two part question (look below)

Question

1) The bedroom of our house is 1,200 cubic meters. We know that there are 3.4 x 10⁹ particles of dust per cubic meter. Write how many particles of dust are present in the bedroom of our house.  

 

2) Find out the weight of 6 billion dust particles, if a dust particle has mass of 7.53 x 10^-10 g

Answer 1

1. the volume of the bedroom is 1,200m³, and there are 3.4 x 10⁹ particles of dust / m³

 

we will convert the room volume to scientific notation = 1.2 x 10³m³

 

then, the total number of particles will be the product of the two numbers, which is 1.2 x 10³m³ times 3.4 x 10⁹ particles/m³ = 4.08 x 10¹² particles

 

2. the weight of 6 billion (6.0 x 10⁹) dust particles multiplied by the weight of each particle (7.53 x 10^-10 gram/particle) will give us the total weight, which will be 45.18 x 10^-1 or 4.518 grams