Question

Calculate the number of protons in 24 gram of SO4^2- at STP

Answer 1

How many moles SO4^2- do you have. That is
mols = grams/molar mass = approx 24/96 = about 0.25
In 1 mol SO4^2- you have 16 protons in S and 8 protons in each oxygen which is a total of 16 + 4(8) = 48. So how many will you have in 0.25 mol? By the way, I assume you are talking about so-called "pure S and pure O); i.e., no isotopes which means we are talking about S-32 and O-16

Answer 2

No I am talking about number of protons in whole molecule i.e., SO4^2- in terms of avogadro's number.

Answer 3

That's what I gave you. The number of protons in that many gams of SO4^2-. However, remember thatS and PO have more than one isotope so you MUST decide which isotopes you have and I am assuming you have S-32 and O-16. To do otherwise means you have a fractional number of protons.

Answer 4

Hmmm??? I thought elements were defined by their atomic numbers ( => # protons) regardless of the isotope. That is, all sulfur isotopes have 16 protons and all oxygen isotopes have 8 protons. The difference is in the number of neutrons which is not the objective of the posted problem. So ...
#p⁺ in 24-g SO₄ˉ² = (1(16) + 4(8)- p⁺/molecule)(6.02 x 10²⁴ molecules/mole) (24-g/98-g/mol) = 7.08 x 10²⁵ p⁺ regardless of the isotopic composition.

Answer 5

Thanks Doc48....
I want that only