Question

3) How many moles are in 22 grams of argon?


4) How many grams are in 88.1 moles of magnesium?


5) How many moles are in 2.3 grams of phosphorus?

6) How many grams are in 11.9 moles of chromium?

7) How many moles are in 9.8 grams of calcium?

8) How many grams are in 238 moles of arsenic?

9) How many grams are in 4.5 moles of NaF?

10) How many moles are in 98.3 grams of Al(OH)3?

11) How many grams are in 0.02 moles of BeI2?

12) How many grams are in 3.3 moles of K2S?

Answer 1

I'll show the molar mass used (approx.) and the calculation for each.

3) How many moles are in 22 g Ar?
- Molar mass Ar ≈ 39.95 g/mol
- moles = 22.0 g / 39.95 g/mol = 0.551 mol

4) How many grams are in 88.1 moles Mg?
- Molar mass Mg ≈ 24.305 g/mol
- mass = 88.1 mol × 24.305 g/mol = 2141 g

5) How many moles are in 2.3 g P?
- Molar mass P ≈ 30.97 g/mol
- moles = 2.3 g / 30.97 g/mol = 0.0743 mol

6) How many grams are in 11.9 moles Cr?
- Molar mass Cr ≈ 52.00 g/mol
- mass = 11.9 mol × 52.00 g/mol = 619 g

7) How many moles are in 9.8 g Ca?
- Molar mass Ca ≈ 40.08 g/mol
- moles = 9.8 g / 40.08 g/mol = 0.245 mol

8) How many grams are in 238 moles As?
- Molar mass As ≈ 74.92 g/mol
- mass = 238 mol × 74.92 g/mol = 1.78 × 10^4 g (≈ 17,831 g)

9) How many grams are in 4.5 moles NaF?
- Molar mass NaF ≈ 22.99 + 19.00 = 41.99 g/mol
- mass = 4.5 mol × 41.99 g/mol = 189 g

10) How many moles are in 98.3 g Al(OH)3?
- Molar mass Al(OH)3 ≈ 26.98 + 3(16.00 + 1.008) = 78.00 g/mol
- moles = 98.3 g / 78.00 g/mol = 1.26 mol

11) How many grams are in 0.02 moles BeI2?
- Molar mass BeI2 ≈ 9.01 + 2(126.90) = 262.81 g/mol
- mass = 0.02 mol × 262.81 g/mol = 5.26 g

12) How many grams are in 3.3 moles K2S?
- Molar mass K2S ≈ 2(39.10) + 32.06 = 110.26 g/mol
- mass = 3.3 mol × 110.26 g/mol = 364 g

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