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2 years ago

A.) What is the mass in g of 5 mols of Mg?

Chemistry

1 answer:

Dovator [93]2 years ago

6 0

Answer:

Mass of Mg = 120 g

1.23 moles of Cu

Explanation:

Given data:

Number of moles of Mg = 5 mol

Mass of Mg = ?

Solution:

Number of moles = mass/molar mass

Molar mass of magnesium is 24 g/mol.

5 mol = mass/ 24 g/mol

Mass = 5 mol × 24 g/mol

Mass = 120 g

B) Given data:

Number of atoms of Cu = 7.4 ×10²³ atom

Number of moles of Cu = ?

Solution:

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. The number 6.022 × 10²³ is called Avogadro number.

1 mole = 6.022 × 10²³ atoms

7.4 ×10²³ atom × 1 mol / 6.022 × 10²³ atom

1.23 moles of Cu

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kvv77 [185]

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3 years ago

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3 years ago

Can some atoms exceed the limits of the octet rule in bonding? If so, give an example.

harkovskaia [24]

Answer:

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Explanation:

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2 years ago

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Answer:

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