Answer:
150.0 mL.
Explanation:
- It is known that the no. of millimoles of HNO₃ before dilution = the no. of millimoles of HNO₃ after dilution.
∵ (MV) before dilution = (MV) after dilution.
<em>∴ V before dilution = (MV) after dilution / M before dilution</em> = (0.15 M)(500.0 mL)/(0.50 M) = <em>150.0 mL.</em>
3 Mg, 0 Fe2O3, 3MgO, 2 Fe
20 g O2 x 1 mol O2/32 g O = 0.625 mol O2
