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How many atoms of oxygen are in 8.43 g of magnesium sulfate heptahydrate (Epsom salts)?How many atoms of oxygen are in 8.43 g of magnesium sulfate heptahydrate (Epsom salts)?

User Chris Cap
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2 Answers

6 votes
moles oxygen = 0.0338 x 11 =0.372
atoms oxygen = 0.372 x 6.02 x 10^23=2.24 x 10^23
moles water = 7 x 0.0338 =0.237
User Reduckted
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Answer: The number of oxygen atoms in given amount of magnesium sulfate heptahydrate is
2.265* 10^(23)

Step-by-step explanation:

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


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

Given mass of magnesium sulfate heptahydrate = 8.43 g

Molar mass of magnesium sulfate heptahydrate = 246.47 g/mol

Putting values in above equation, we get:


\text{Moles of magnesium sulfate heptahydrate}=(8.43g)/(246.47g/mol)=0.0342mol

The chemical formula of magnesium sulfate heptahydrate is
MgSO_4.7H_2O

1 mole of magnesium sulfate heptahydrate contains 1 mole of magnesium atoms, 1 mole of sulfur atoms, 11 moles of oxygen atoms and 14 moles of hydrogen atoms

According to mole concept:

1 mole of a compound contains
6.022* 10^(23) number of particles

So, 0.0342 moles of magnesium sulfate heptahydrate will contain =
(11* 0.0342* 6.022* 10^(23))=2.265* 10^(23) number of oxygen atoms

Hence, the number of oxygen atoms in given amount of magnesium sulfate heptahydrate is
2.265* 10^(23)

User Mager
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