Determining Mass of Lithium

Question

What is the mass of 1.3 x 10^(23) atoms of lithium.

Lithium has a mass of 6.94, so I assumed that it'd be 6.94 x 1.3 x 10^(23), but that wasn't the case. I wasn't given much practice and I'm not sure how to proceed.

Any advice in the right direction is greatly appreciated.

I'm voting to close this question as off-topic because it's a chemistry/physics question. — Glorfindel, Jul 04 '17 at 07:44

score 1 · Accepted Answer · answered Jul 04 '17 at 07:30

1

Look up Avogadro's number and the definition of a mole (unit). $6.022\cdot 10^{23}$ atoms with atomic mass of 6.94 will have a total mass of 6.94 grams. By taking a simple ratio, you can figure out how much mass have $1.3\cdot 10^{23}$ atoms

answered Jul 04 '17 at 07:30

Andrei

37,370

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So 1.3 x 6.94 = 9.022/6.022 = 1.498, which is the correct answer? – Grimestock Jul 04 '17 at 07:36
Yes, but just write it as 1.3 x 6.94/6.022 – Andrei Jul 04 '17 at 14:26

Determining Mass of Lithium

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