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[H2C2O4.2H2O] = weight / Mw / V(L) ⇒ x × 10−2 = 6.3/126 / (250/1000) ⇒ x = 20

1. 10
2. 20
3. 30
4. 40

Correct answer: 20

Solution

The calculation shows that when the weight of the substance is divided by its molar mass and then divided by the volume in liters, the resulting concentration is equal to 20 when solved correctly.

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