Answer: Each ion, or atom, has a particular mass; similarly, each mole of a given pure substance also has a definite mass. The mass of one mole of atoms of a pure element in grams is equivalent to the atomic mass of that element in atomic mass units (amu) or in grams per mole (g/mol).
Explanation:
We will get the molality from this formula:
Molality = no.of moles of solute / Kg of solvent
So first we need the no.of moles of KNO3 = the mass of KNO3 / molar mass of KNO3
no.of moles of KNO3 = 175 / 101.01 = 1.73 mol
By substitution in the molality formula:
∴ molality = 1.73 / (750/1000) = 2.3 Molal
Answer:
2Fe + O₂ -------------------> 2FeO
8 mol Fe produce
8 mol Fe * 2 mol FeO / 2 mol Fe = 8 mol FeO
Mass of FeO = 8 mol FeO * 71.85 g/mol = 574.8 grams FeO
Explanation:
Having 8 mol of Iron means 8 moles of iron oxide can be produced. Each mole of iron oxide has a molecular weight of 71.85 grams. Therefore, 8 moles of iron oxide should weight 574.8 grams.
I think the answer is three but i can't be sure.