a) 5.16 x 10 ^30
b) 3.01 x 10 ^23
c) 1.20 x 10 ^24
d) 1.10 x 10 ^28
explain please
2007-04-07 11:16:43 · 4 answers · asked by Anonymous in Science & Mathematics ➔ Chemistry
97.6g Pt*(1mole Pt/195.08gPt)*(6.02x10^23 atom/1mole Pt)= 3.01x10^23
answer is b
2007-04-07 11:27:41 · answer #1 · answered by Helper 6 · 0⤊ 0⤋
Take a periodic table, find the weight of the Pt.
Found ? it's 195.084 of course.
You know what is avogadro number ? you should if you are asking this question, probably you are studying stechiometry for a biology or chemistry course.
Avogadro is = 6.0221415 Ã 10^23
So find the moles in 97.6 g of Pt then multiply per avogadro number to find the number of atoms.
answers are:
0.5 moles (more or less)
correct answer is b)
(I don't even need a calculator, it's too easy)
2007-04-07 18:27:18 · answer #2 · answered by scientific_boy3434 5 · 0⤊ 0⤋
Please note that the molar mass of an element contain 6.02 x 10^23 atoms.
195 g (molar mass of Pt) contain 6.02 x 10^23 atoms
therefore 97 g contain 97/195 x 6.02 x 10^23
= 2.99 x 10^23
The answer closest to the calculated is b.
2007-04-07 18:43:33 · answer #3 · answered by brisko389 3 · 0⤊ 0⤋
Take the mass and convert that to moles by dividing by the atomic weight of Pt. Then, convert moles into atoms by multiplying by Avogadro's number.
2007-04-07 18:26:38 · answer #4 · answered by hcbiochem 7 · 0⤊ 0⤋