Practical 7.1: Tests for Gases

What is the expected observation when hydrogencarbonate indicator is added to tube tube filled with oxygen and shaken?

What happens to the glowing splint when it is placed into a tube with oxygen?

What should occur to lime water inside a test tube when exposed to carbon dioxide ?

Which gas is identified if a glowing splint reignites upon insertion into a test tube?

What characteristic of nitrogen would be observed in the experiments?

What safety precaution is specifically mentioned for handling gases in this experiment?

What is the purpose of using a glowing splint in the experiment?

What is the main use of hydrogencarbonate indicator in the experiment?

What material is used to identify carbon dioxide in the experiment?

How does the smell of the gases in tubes F to J compare to those in K to O?

Which test is performed to check the presence of oxygen in the experiment?

What should be done immediately after lighting the wooden splint for the oxygen test?

Which gas is indicated by the use of lime water in the experiment?

In the context of the experiment, why is it important to act quickly during gas testing?

Practical 7.1: Tests for Oxygen, Carbon Dioxide, and Nitrogen

Aim: To develop tests for identifying oxygen, carbon dioxide, and nitrogen.

Apparatus and Materials

Per Group:
- Wooden splint: 6
- Test tube rack: 1
- Test tube filled with oxygen: 5
- Gas lighter: 1
- Test tube filled with carbon dioxide: 5
- Hydrogencarbonate indicator: 1
- Test tube filled with nitrogen: 5
- Lime water: 1
Safety Spectacles Required

Part I: Oxygen

Procedure 1: Teacher provides five test tubes labeled A to E with oxygen.
Procedure 2: Observe the gas in tube A and record the color in a table.
Procedure 3: Remove stopper from tube A. Fan the gas towards your nose and record the smell.

Part I: Oxygen (Continued)

Procedure 4: Light a wooden splint and introduce it into a test tube of oxygen. Note the observation.
Procedure 5: Light a wooden splint, blow out the flame to create a glowing splint and introduce it into another test tube of oxygen. Note the observation.

Part II: Carbon Dioxide

Procedure: Repeat the procedures in part 1, using test tubes labeled F through J containing carbon dioxide.

Part III: Nitrogen

Procedure: Repeat the procedures in part 1, using test tubes labeled K through O containing nitrogen.

Results

Oxygen: Colorless, odorless. Burning splint burns more brightly. Glowing splint relights.
Carbon Dioxide: Colorless, odorless. Burning splint goes out. Glowing splint goes out . Hydrogencarbonate indicator changes from red to yellow. Limewater turns milky.
Nitrogen: Colorless, odorless. Burning splint goes out. Glowing splint goes out. No significant change with hydrogencarbonate indicator or limewater.

Discussion

Identifying Oxygen: Glowing splint will relight. Burning splint will burn more brightly.
Identifying Carbon Dioxide: Hydrogencarbonate indicator turns from red to yellow. Limewater turns milky.
Identifying Nitrogen: No readily available, simple identification test.

This quiz focuses on the practical experiments designed to identify oxygen, carbon dioxide, and nitrogen through various tests. It includes procedures for observing gases, recording observations, and using indicators. Safety precautions and the necessary apparatus for conducting these tests are also outlined.