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3 years ago

How many particles of Na are there in 1.43g of a molecular compound with a Molar mass of 23g?

Chemistry

1 answer:

Olin [163]3 years ago

7 0

Answer:

3.74 x 10²² particles

Explanation:

Given parameters:

Mass of compound = 1.43g

Molar mass of compound = 23g

Unknown:

Number of particles of sodium = ?

Solution:

To find the number of particles of Na in the compound, we need to obtain the mass of sodium from the total mass given;

Mass of sodium = $\frac{molar mass of Na}{molar mass of compound} x mass of sample$

= $\frac{23}{23} x 1.43g$

= 1.43g

Now find the number of moles of this amount of Na in the sample;

Number of moles = $\frac{mass}{molar mass}$ = $\frac{1.43}{23}$ = 0.062mole

Now;

1 mole of substance = 6.02 x 10²³ particles

0.062 mole of substance = 0.062 x 6.02 x 10²³ particles

= 3.74 x 10²² particles

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