Since the iron is pure, we can look up its density value online and will always be true. This density value of iron is 7.87g/L. Now, we can use the density formula (D = m/V) and rearrange it to solve for V. This new equation is then V = m/D. Next, we plug in our known values and solve for V (5.00g/7.87g/L). This gives us our final answer of 0.635L (three sig figs due to the three sig figs in the provided mass).
Hope this helps!
