How many atoms of copper are present in 46 nanograms of copper?

1 ⤊

How many atoms of copper are present in 46 nanograms of copper?

2007-09-01 18:54:19 · 3 answers · asked by Anonymous in Science & Mathematics ➔ Chemistry

3 answers

46 nanograms = 0.0000000046 g

Atomic weight of Copper is 63.546 g/mol

Moles Cu = 0.000000046 g / 63.456 = 7.25 x 10^-10

1 mole ==> 6.02 x 10^23 atoms

7.25 x 10^-10 x 6.02 x 10^23 = 4.36 x 10^14 atoms

2007-09-02 01:23:13 · answer #1 · answered by Dr.A 7 · 0⤊ 1⤋

lmao... I never thought of posting 'homework' questions on here. Props to you. I could try and stir up memories of
Avogadro's number and the Periodic Table of Elements, but I think I'll leave that to you in your chemistry course.

2007-09-02 02:12:12 · answer #2 · answered by cuatrosinko 1 · 1⤊ 0⤋

46*6.023/63.5 * 10^14 atoms.

2007-09-02 02:00:44 · answer #3 · answered by ag_iitkgp 7 · 0⤊ 2⤋