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3 years ago

How many atoms are in 2.10 g of K? molar mass of K=39.10g/mole.

Chemistry

1 answer:

Alborosie3 years ago

5 0

Answer:

<h3>The answer is option B</h3>

Explanation:

To calculate the number of atoms we must first calculate the number of moles

Molar mass = mass / number of moles

number of moles = mass / Molar mass

Molar mass (K) = 39.10mole

mass = 2.10g

number of moles = 2.10/ 39.10

= 0.0537mol

After that we use the formula

N = 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 × 10^23 entities

Number of K atoms is

N = 0.0537 × 6.02 × 10^13

<h3>N = 3.23×10^22 atoms of K</h3>

Hope this helps you.

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3 years ago