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tatuchka [14]
3 years ago
7

How many atoms is 50 g of He?

Chemistry
1 answer:
tigry1 [53]3 years ago
6 0
Atomic <span>mass He = 4.002 u.m.a

4.002 g --------------- 6.02x10</span>²³ atoms
50 g ------------------ ? atoms

50 x ( 6.02x10²³) / 4.002

= 3.01x10²⁵ / 4.002

= 7.52x10²⁴ atoms of He
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3 years ago
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