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
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
8.2×10−20
8 point 2 times 10 to the negative 20 power
1.2×1021
1.2×1021
why wouldn't it be 8.2*10^20
To calculate the number of electrons needed to equal the mass of a dust particle, we need to divide the mass of the dust particle by the mass of a single electron.
Given:
Mass of a dust particle = 7.5×10^-10 kg
Mass of an electron = 9.1×10^-31 kg
Number of electrons = (Mass of dust particle) / (Mass of an electron)
Number of electrons = (7.5×10^-10 kg) / (9.1×10^-31 kg)
Number of electrons = 8.2×10^20
Therefore, it would indeed be 8.2x10^20 electrons needed to equal the mass of a dust particle, not 8.2x10^-20 as in one of the answer choices. Thank you for pointing that out, the correct answer is 8.2x10^20. Apologies for the oversight.