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aev [14]
3 years ago
13

How many atoms are in a sample of 72.8 grams calcium ?

Chemistry
1 answer:
MArishka [77]3 years ago
6 0
First find the moles
moles of the calcium= 72.8 / 40
moles of calcium in 72.8g = 1.82mol

number of atoms= moles x Avogadro constant
atoms = 1.82 x 6.02x10+23
so the number of atoms is 1.096x10+24
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What is the ph of a 0.0055 m ha (weak acid) solution that is 8.2% ionized?
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Answer is: pH value of weak is 3.35.
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c(HA) = 0.0055 M.
α = 8.2% ÷ 100% = 0.082.
[H⁺] = c(HA) · α.
[H⁺] = 0.0055 M · 0.082.
[H⁺] = 0.000451 M.
pH = -log[H⁺].
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3 0
3 years ago
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Nimfa-mama [501]

Answer:

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Explanation:

We calculate the weight of 1 mol of H3PO4:

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1 mol-----98 grams H3PO4

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4 0
3 years ago
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EastWind [94]
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m_a_m_a [10]
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astra-53 [7]

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3 0
3 years ago
Read 2 more answers
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