RoseMarie Gallagher and Paul Ingram Solutions for Chapter: Reacting Masses, and Chemical Equations, Exercise 5: Checkup on Chapter 5

This shows the structure of a molecular compound. Name the compound.

This shows the structure of a molecular compound. What is the simplest formula of it?

Calculate the relative formula mass for the ionic compound Potassium carbonate, ${\mathrm{K}}_2{\mathrm{CO}}_3$.

Calculate the relative formula mass for the ionic compound hydrated Iron $\left(\mathrm{II}\right)$ sulphate, ${\mathrm{FeSO}}_4.7{\mathrm{H}}_2\mathrm{O}$.

Aluminium is extracted from the ore Bauxite, which is impure Aluminium oxide. $1 \mathrm{tonne} \left(1000 \mathrm{kg}\right)$ of the ore was found to have this composition: 

Aluminium oxide $\left(825 \mathrm{kg}\right)$, Iron $\left(\mathrm{III}\right)$ oxide $\left(100 \mathrm{kg}\right)$ and sand $\left(75 \mathrm{kg}\right)$

What percentage of this ore has impurities?

Aluminium is extracted from the ore Bauxite, which is impure Aluminium oxide. $1 \mathrm{tonne} \left(1000 \mathrm{kg}\right)$ of the ore was found to have this composition: 

Aluminium oxide $\left(825 \mathrm{kg}\right)$, Iron $\left(\mathrm{III}\right)$ oxide $\left(100 \mathrm{kg}\right)$ and sand $\left(75 \mathrm{kg}\right)$.

$1 \text{tonne}$ of ore gives $437 \mathrm{kg}$ of Aluminium. How much aluminium will be obtained from $5 \mathrm{tonnes}$ of the ore?

Aluminium is extracted from the ore Bauxite, which is impure Aluminium oxide. $1 \mathrm{tonne} (1000 \mathrm{kg})$ of the ore was found to have this composition: 

Aluminium oxide $\left(825 \mathrm{kg}\right)$, Iron $\left(\mathrm{III}\right)$ oxide $\left(100 \mathrm{kg}\right)$ and sand $\left(75 \mathrm{kg}\right)$

$1 \mathrm{tonne}$ of ore gives $437 \mathrm{kg}$ of Aluminium. What mass of sand is in this $5 \mathrm{tonnes}$?

Aluminium is extracted from the ore Bauxite, which is impure Aluminium oxide. $1 \mathrm{tonne} (1000 \mathrm{kg})$  of the ore was found to have this composition: 

Aluminium oxide $\left(825 \mathrm{kg}\right)$, Iron $\left(\mathrm{III}\right)$ oxide $\left(100 \mathrm{kg}\right)$ and sand $\left(75 \mathrm{kg}\right)$.

What will be the percentage of Aluminium oxide in the ore, if all the Iron $\left(\mathrm{III}\right)$ oxide is removed, leaving only the Aluminium oxide and sand?