Answer: 122 moles
Procedure:
1) Convert all the units to the same unit
2) mass of a penny = 2.50 g
3) mass of the Moon = 7.35 * 10^22 kg (I had to arrage your numbers because it was wrong).
=> 7.35 * 10^22 kg * 1000 g / kg = 7.35 * 10^ 25 g.
4) find how many times the mass of a penny is contained in the mass of the Moon.
You have to divide the mass of the Moon by the mass of a penny
7.35 * 10^ 25 g / 2.50 g = 2.94 * 10^25 pennies
That means that 2.94 * 10^ 25 pennies have the mass of the Moon, which you can check by mulitiplying the mass of one penny times the number ob pennies: 2.50 g * 2.94 * 10^25 = 7.35 * 10^25.
5) Convert the number of pennies into mole unit. That is using Avogadros's number: 6.022 * 10^ 23
7.35 * 10^ 25 penny * 1 mol / (6.022 * 10^ 23 penny) = 1.22* 10^ 2 mole = 122 mol.
Answer: 122 mol
Answer: 3.57M
Explanation:Please see attachment for explanation
The Molarity of a solution = number of moles / volume.
Volume = 244ml = 0.244L
So it follows that number of moles = Molarity * volume
Number of moles = 0.135 * 0.244 = 0.03945.
Hence the number of moles = 0.03945
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=
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= 0.134 mol
mol of oxygen:
ratio of
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= 2 : 15
= 1 : 7.5
: . mol of
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= 0.134mol * 7.5
= 1.01 mol
Mass of Oxygen = mol * Mr
= 1.01 mol * (16*2) g/mol
= 32.22g
Note: Mr is molar mass