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A student investigates the solubility of four metal oxides and four non-metal oxides in water. The student tests the [tex][tex]$pH$[/tex][/tex] of the solutions formed. The table shows the student's results.

\begin{tabular}{|l|c|c|c|}
\hline
Type of oxide & Oxide & Solubility in water & [tex][tex]$pH$[/tex][/tex] of solution \\
\hline
\multirow{3}{}{Metal oxides} & Sodium oxide & Soluble & 14 \\
\cline{2-4} & Calcium oxide & Soluble & 10 \\
\cline{2-4} & Magnesium oxide & Slightly soluble & 9 \\
\hline
\multirow{3}{}{Non-metal oxides} & Zinc oxide & Insoluble & No solution formed \\
\cline{2-4} & Carbon dioxide & Soluble & 5 \\
\cline{2-4} & Phosphorus oxide & Soluble & 2 \\
\hline
Silicon dioxide & Insoluble & No solution formed \\
\hline
\end{tabular}

The student makes two conclusions:
1. 'All metal oxides produce alkaline solutions.'
2. 'All non-metal oxides produce acidic solutions.'

Explain why the student's conclusions are only partly correct. Use information from the table above.



Answer :

GinnyAnswer
To assess the accuracy of the student's conclusions, we need to verify each statement using the data from the provided table.

Conclusion 1: 'All metal oxides produce alkaline solutions.'

### Analysis of Metal Oxides:
- Sodium oxide:
- Solubility: Soluble
- pH of solution: 14 (Alkaline)
- Calcium oxide:
- Solubility: Soluble
- pH of solution: 10 (Alkaline)
- Magnesium oxide:
- Solubility: Slightly soluble
- pH of solution: 9 (Alkaline)

Given the data:
- Sodium oxide, Calcium oxide, and Magnesium oxide all produce alkaline solutions, as their pH values are greater than 7.

Thus, Conclusion 1 is correct for the given examples as all the mentioned metal oxides in the table produce alkaline solutions.

Conclusion 2: 'All non-metal oxides produce acidic solutions.'

### Analysis of Non-Metal Oxides:
- Zinc oxide:
- Solubility: Insoluble
- pH of solution: No solution formed (Cannot be classified as acidic or alkaline)
- Carbon dioxide:
- Solubility: Soluble
- pH of solution: 5 (Acidic)
- Phosphorus oxide:
- Solubility: Soluble
- pH of solution: 2 (Acidic)
- Silicon dioxide:
- Solubility: Insoluble
- pH of solution: No solution formed (Cannot be classified as acidic or alkaline)

Given the data:
- Carbon dioxide and Phosphorus oxide produce acidic solutions, as their pH values are less than 7.
- Zinc oxide and Silicon dioxide are insoluble and do not form solutions, so they cannot be characterized by a pH value.

Thus, Conclusion 2 is correct for the given examples, but with the important clarification that Zinc oxide and Silicon dioxide, being insoluble, do not actually form solutions that could be tested for acidity.

### Final Assessment:
- Conclusion 1 is fully correct based on the given data.
- Conclusion 2 is also correct for the soluble non-metal oxides, but it should be noted that insoluble oxides like Zinc oxide and Silicon dioxide do not form solutions to determine their acidity.

Therefore, the conclusions are mostly accurate but need slight modification for completeness regarding the insolubility aspect of some non-metal oxides.

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