Question

Describe how you would prepare crystals of sodium nitrate starting with 200cm3 of 2M sodium hydroxide.

Answer 1

To prepare crystals of sodium nitrate, start with 200cm³ of 2M sodium hydroxide. Heat the sodium hydroxide and add nitric acid to lower the pH. Allow the solution to cool and filter out the crystals. Rinse and dry them.

Step-by-step explanation:

To prepare crystals of sodium nitrate starting with 200cm3 of 2M sodium hydroxide, we can use a method called precipitation. Here are the steps:

1. Carefully measure out 200cm3 of 2M sodium hydroxide into a beaker.
2. Heat the sodium hydroxide solution in a water bath or on a hot plate until it reaches a temperature slightly below boiling.
3. Add small amounts of nitric acid to the sodium hydroxide solution, while stirring constantly, until the pH of the solution drops to around 7-8.
4. Allow the solution to cool slowly. Over time, crystals of sodium nitrate will begin to form.
5. Filter the solution to separate the crystals from the remaining liquid.
6. Rinse the crystals with a small amount of cold distilled water to remove any impurities.
7. Dry the crystals by placing them on a piece of filter paper and leaving them in a cool, dry place.