Question

Question

The mass of a dust particle is approximately 7.5×10−10
kilograms and the mass of an electron is 9.1×10−31
kilograms. Which expression would you use to find out how many electrons you need to equal the mass of one dust particle?(1 point)
Responses

(7.5×10−10)÷(9.1×10−31)
open paren 7 point 5 times 10 to the negative 10 power close paren divided by open paren 9 point 1 times 10 to the negative 31 power close paren

(9.1×10−31)−(7.5×10−10)
open paren 9 point 1 times 10 to the negative 31 power close paren minus open paren 7 point 5 times 10 to the negative 10 power close paren

(9.1×10−31)(7.5×10−10)
open paren 9 point 1 times 10 to the negative 31 power close paren times open paren 7 point 5 times 10 to the negative 10 power close paren

(7.5×10−10)(9.1×10−31)
open paren 7 point 5 times 10 to the negative 10 power close paren times open paren 9 point 1 times 10 to the negative 31 power close paren

(9.1×10−31)÷(7.5×10−10)
open paren 9 point 1 times 10 to the negative 31 power close paren divided by open paren 7 point 5 times 10 to the negative 10 power close paren

Answer 1

To find out how many electrons are needed to equal the mass of one dust particle, you need to divide the mass of the dust particle by the mass of one electron.

The expression you would use is:

\[ (7.5 \times 10^{-10}) \div (9.1 \times 10^{-31}) \]

This corresponds to the first response in your list:

(7.5×10−10)÷(9.1×10−31)