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2 years ago

4.5 × 1025 atoms of nickel equal how many moles? A. 27 mol B. 2.7 × 1048 mol C. 0.75 mol D. 75 mol

Chemistry

2 answers:

crimeas [40]2 years ago

7 0

Answer:

75 mol

Explanation:

The number of atoms in a mole of substance is 6.023X10²³ [Avagadro's number]

if the given sample of nickel contains 4.5X10²⁵ atoms it means the moles are

moles = $\frac{numberofatoms}{Avagadro'snumber}$

moles = $\frac{4.5X10^{25}}{6.023X^{23}}=74.71mol$

If we round of the given answer the number of moles = 75 moles

Molodets [167]2 years ago

4 0

It's 75
PS use ^ to mean to the power of

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jek_recluse [69]

The question is incomplete, here is the complete question:

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