Iron has a density of 7.87 g/cm3. What is the volume in cm3 of 3.729 g of iron?

Both models are effective because they show the valence electrons, and these valence electrons indicate the reactivity of an element.

Molarity is moles of solute over liters of solution. idk if that is what you are talking about, but you can convert moles of solute to grams of solute using dimensional analyzes by using molar mass found on the periodic table.

Heat of fusion= heat/mass  heat of fusion = 12.03kj/36 g= 0.3342 kj/g or 334.2 j/g