Materials required:

Procedure:

As performed in a real lab:

• Take a small quantity of calcium oxide (quick lime) in a beaker.
• Slowly add water to the quick lime taken in the beaker. Pour enough water so that the quick lime remains submerged in the water.
• Touch the beaker with fingers to note the temperature.
• Leave the beaker undisturbed for some time.
• Take a small quantity of clear solution from the beaker in a test tube and blow exhaled air into the lime water.

Simulator Procedure (as performed through the Online Labs)

• Drag the spatula containing quicklime over to the empty beaker to transfer the contents into it.
• Drag the beaker containing distilled water to pour it into the beaker containing quick lime.
• Wait for some time till the quick lime reacts with water to form a suspension of slaked lime.
• You can see that the thermometer shows an increase in temperature.
• View the inference by clicking on the inference icon.
• Click on the ‘Next’ button to go to the next process.
• You will get a clear solution of lime water as the suspension of slaked lime settles down at the bottom of the beaker.
• Now, drag the dropper and dip it in the beaker to suck lime water in it and then drag it towards the test tube to pour the lime water into it.
• Drag the cork with the bent tube towards the test tube to close it.
• Click on the ‘Next’ button to go to the next process.
• Click on the blow button to blow in exhaled air into the test tube containing lime water.
• The lime turns milky.
• View the inference by clicking on the inference icon.
• You can click on the ‘Reset’ button to redo the experiment.

Note: Click on the ‘HELP’ button to see the instructions

Observations:

• When water is added to quick lime, a suspension of slaked lime is formed.
• On touching the beaker we feel it is hot.
• A clear solution appears as the suspension of slaked lime settles down to the bottom of the beaker.
• On blowing exhaled air that contains sufficient carbon dioxide, lime water turns milky.

Inferences:

• Quick lime reacts vigorously with water to produce slaked lime releasing a large amount of heat. So the reaction is highly exothermic.

• Slaked lime is only slightly soluble in water, so it forms a suspension of slaked lime in water.
• The clear solution obtained after the suspension settles is called lime water.
• Exhaled air contains CO2 which turns lime water milky.
• Calcium oxide and water react to form only a single product, calcium hydroxide. So the reaction is a combination reaction.

Precautions:

Enjoy your experiment!!