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How many phosphorus atoms are contained in 158 kg of phosphorus

User Kalley
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1 Answer

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Step 1 - First, we need to transform kg into g. We need to multiply it by 1000:

158 kg = 158,000 g of phosphorus

Step 2 - Now we need to know the molar mass of phosphorus. Look for it at the periodic table. It is 30.97 g/mol.

Step 3 - We transform grams into moles:

30.97 g ---- 1 mol

158,000 g ---- x mol

x = 5,101.7 moles of phosphorus

Step 4 - We transform moles into atoms using Avogrado's constant:

6.022 x 10^23 ---- 1 mol

x ---- 5,101.7 moles of phosphorus

x = 3.072 x 10^27 atoms

If you want to calculate it in another way:

158000/30.97 x 6.022 x 10^23 = 3.072 x 10^27 atoms

Answer: There are 3.072 x 10^27 atoms of phosphorus

User Villu Sepman
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