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?
To find out how many electrons are needed to equal the mass of one dust particle, you can use the following expression:
(number of electrons) = (mass of dust particle) / (mass of one electron)
(number of electrons) = 7.5×10^−10 kg / 9.1×10^−31 kg
(number of electrons) = (7.5×10^−10 kg) / (9.1×10^−31 kg)
(number of electrons) = (7.5 / 9.1) × 10^(−10-(-31))
(number of electrons) = 0.825 × 10^21
Therefore, you would need approximately 8.25×10^20 electrons to equal the mass of one dust particle.