Answer :
Given that the mass of proton = 1.67 x 10⁻²⁴ grams.
Therefore, if there are 1000 protons, the whole mass will be
1000 protons * 1.67 x 10⁻²⁴ = 1.67 x 10⁻²¹ grams
Therefore, if there are 1000 protons, the whole mass will be
1000 protons * 1.67 x 10⁻²⁴ = 1.67 x 10⁻²¹ grams