5.00 g of magnesium represents how many moles?

Chemistry

2 answers:

OleMash [197]4 years ago

8 0

Answer: The number of moles of magnesium in given amount is 0.2056 moles.

Explanation:

To calculate the number of moles, we use the equation:

$\text{Number of moles}=\frac{\text{Given mass}}{\text{Molar mass}}$

We are given:

Given mass of magnesium = 5 g

Molar mass of magnesium = 24.31 g/mol

Putting values in above equation, we get:

$\text{Moles of magnesium}=\frac{5g}{24.31g/mol}=0.2056mol$

Hence, the number of moles of magnesium in given amount is 0.2056 moles.

Nastasia [14]4 years ago

5 0

Number of moles = mass / molecular mass

Molecular mass of Mg = 24.3 g/mol

n = 5g / 24.3 g/mol
= 0.206 moles

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