How many moles of Ca are in 7.2x10^25 molecules of Ca (show work)

Chemistry

1 answer:

Gre4nikov [31]3 years ago

5 0

Answer:

<h2>119.60 moles</h2>

Explanation:

To find the number of moles in a substance given it's number of entities we use the formula

$n = \frac{N}{L} \\$

where n is the number of moles

N is the number of entities

L is the Avogadro's constant which is

6.02 × 10²³ entities

From the question we have

$n = \frac{7.2 \times {10}^{25} }{6.02 \times {10}^{23} } \\ =119.60132...$

We have the final answer as

<h3>119.60 moles</h3>

Hope this helps you

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