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. How many electrons does it take to equal the mass of a dust particle?(1 point) Responses 6.8×10−40 6 point 8 times 10 to the negative 40 power 8.2×10−20 8 point 2 times 10 to the negative 20 power 6.8×10−41 6 point 8 times 10 to the negative 41 power 1.2×10−21 1 point 2 times 10 to the negative 21 power 8.2×1020 8 point 2 times 10 to the 20th power 1.2×1021

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. How many electrons does it take to equal the mass of a dust particle?(1 point) Responses 6.8×10−40 6 point 8 times 10 to the negative 40 power 8.2×10−20 8 point 2 times 10 to the negative 20 power 6.8×10−41 6 point 8 times 10 to the negative 41 power 1.2×10−21 1 point 2 times 10 to the negative 21 power 8.2×1020 8 point 2 times 10 to the 20th power 1.2×1021

Answer 1

To find how many electrons it takes to equal the mass of a dust particle, we can divide the mass of the dust particle by the mass of one electron:

(7.5×10^-10 kg) / (9.1×10^-31 kg/electron) = 8.24×10^20 electrons

Therefore, it takes approximately 8.24×10^20 electrons to equal the mass of a dust particle.

The closest answer is 8.2×10^20, so the correct choice would be:

8.2×10^20