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3 years ago

-) How many atoms are in 0.58 mol of Se?

Chemistry

1 answer:

FinnZ [79.3K]3 years ago

5 0

Answer:

3.50 × 10²³ Atoms of Se

Explanation:

As we know that 1 mole of any substance contains exactly 6.022 × 10²³ particles which is also called as Avogadro's Number. So in order to calculate the number of particles (atoms) contained by 0.580 moles of Se, we will use following relation,

Moles = Number of Atoms ÷ 6.022 × 10²³ Atoms.mol⁻¹

Solving for Number of Atoms,

Number of Atoms = Moles × 6.022 × 10²³ Atoms.mol⁻¹

Putting values,

Number of Atoms = 0.580 mol × 6.022 × 10²³ Atoms.mol⁻¹

Number of Atoms = 3.50 × 10²³ Atoms

Hence,

There are 3.50 × 10²³ atoms present in 0.280 moles of Se.

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Since you have been given choices, my sloppy numbers will do, but it anyone is going to see this, YOU SHOULD CLEAN THEM UP WITH THE NUMBERS THAT COME FROM YOUR PERIODIC TABLE.

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Sodium Phosphate + Calcium Chloride ===> Sodium Chloride + Calcium Phosphate.

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Short Answer C

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2HCl + Mg ===> H2 + MgCl2

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The balanced equation tells you that for ever mole of H2 produced, you need 2 moles of HCl. That's what the balance numbers are for.

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-) How many atoms are in 0.58 mol of Se?​

-) How many atoms are in 0.58 mol of Se?