<p>How many moles of&nbsp;<math xmlns="http://www.w3.org/1998/Math/MathML"><mi>F</mi><msup><mi>e</mi><mrow><mn>2</mn><mo>+</mo></mrow></msup></math>&nbsp;ions are formed, when excess of iron is treated with 50 mL of 4.0 M HCl under inert atmosphere? Assume no change in volume:</p>