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How many molecules of Acetic Acid (CH3COOH) are in a sample that has a mass of 172.90 g?

User Flaashing
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1 Answer

7 votes

Answer:

17.46× 10²³ molecules

Step-by-step explanation:

Given data:

Mass of acetic acid = 172.90 g

Number of molecules = ?

Solution:

First of all we will calculate the number of moles of acetic acid :

Number of moles = mass / molar mass

Number of moles = 172.90 g/ 60.1 g/ol

Number of moles = 2.9 mol

Now the given problem will solve by using Avogadro number.

The number 6.022 × 10²³ is called Avogadro number.

1 mole = 6.022 × 10²³ molecules

2.9 mol × 6.022 × 10²³ molecules / 1 mol

17.46× 10²³ molecules

Avogadro number:

It is the number of atoms , ions and molecules in one gram atom of element, one gram molecules of compound and one gram ions of a substance.

User Walter Johnson
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