Nsubuga writes down the hazards of the investigation. Complete the table to show how he can control the risks from these hazards.

\begin{tabular}{|l|l|}
\hline
Hazard & How to control risks from the hazards \\
\hline
Magnesium is highly flammable/can catch fire & \\
\hline
Burning magnesium has a very bright flame & \\
\hline
\end{tabular}

c) Nsubuga writes down his results as follows:
- Mass of crucible + lid [tex]$=32.00 \, \text{g}$[/tex]
- Mass of magnesium [tex]$=0.24 \, \text{g}$[/tex]
- Mass of crucible + lid + magnesium oxide [tex]$=32.40 \, \text{g}$[/tex]

i) Calculate the mass of magnesium oxide formed (2 points)

ii) Calculate the mass of oxygen that combined with magnesium in the experiment (2 points)



Answer :

Let's proceed step by step.

### Part (i): Calculate the mass of magnesium oxide formed

To find the mass of magnesium oxide formed, we need to consider the given data:

- Mass of crucible + lid = [tex]\( 32.00 \, \text{g} \)[/tex]
- Mass of crucible + lid + magnesium oxide = [tex]\( 32.40 \, \text{g} \)[/tex]

The mass of magnesium oxide formed can be found by subtracting the mass of the crucible and lid from the mass of the crucible, lid, and magnesium oxide:

[tex]\[ \text{Mass of magnesium oxide} = \text{Mass of crucible + lid + magnesium oxide} - \text{Mass of crucible + lid} \][/tex]

By substituting the values:

[tex]\[ \text{Mass of magnesium oxide} = 32.40 \, \text{g} - 32.00 \, \text{g} \][/tex]

[tex]\[ \text{Mass of magnesium oxide} = 0.40 \, \text{g} \][/tex]

### Part (ii): Calculate the mass of oxygen that combined or joined with magnesium in the experiment

We know the given data:

- Mass of magnesium = [tex]\( 0.24 \, \text{g} \)[/tex]
- Previously calculated mass of magnesium oxide = [tex]\( 0.40 \, \text{g} \)[/tex]

The mass of oxygen that combined with magnesium can be found by subtracting the mass of magnesium from the mass of magnesium oxide:

[tex]\[ \text{Mass of oxygen} = \text{Mass of magnesium oxide} - \text{Mass of magnesium} \][/tex]

By substituting the values:

[tex]\[ \text{Mass of oxygen} = 0.40 \, \text{g} - 0.24 \, \text{g} \][/tex]

[tex]\[ \text{Mass of oxygen} = 0.16 \, \text{g} \][/tex]

### Summary:
i) The mass of magnesium oxide formed is [tex]\( 0.40 \, \text{g} \)[/tex].

ii) The mass of oxygen that combined with magnesium in the experiment is [tex]\( 0.16 \, \text{g} \)[/tex].