Expert Chemistry Tutoring

Q1. Knowledge Recall (1 mark)

Define the term "effusion".

Q2. Application (2 marks)

Explain why oxygen gas is essential for human life.

Q3. Knowledge Recall (2 marks)

What is the name of the test used to distinguish between carbon dioxide and sulfur dioxide gases?

Q4. Data Analysis (3 marks)

A sample of gas occupies a volume of 250 cm³ at room temperature and pressure. The gas is transferred to a new container at the same temperature but at a pressure of 800 mmHg. Calculate the new volume of the gas.

Q5. Application (2 marks)

Describe the role of hydrogen gas in a fuel cell.

Q6. Knowledge Recall (1 mark)

What color turns litmus paper when chlorine gas is bubbled through water?

Q7. Calculations (4 marks)

A 100 cm³ sample of ethane gas (C2H6) is burned in excess oxygen. Write the balanced chemical equation for this reaction and calculate the volume of oxygen required at room temperature and pressure.

Q8. Knowledge Recall (1 mark)

What is the name of the instrument used to measure the volume of gas collected in various reactions?

Q9. Application (3 marks)

Explain how the solubility of carbon dioxide in water is affected by an increase in temperature and the partial pressure of carbon dioxide.

Q10. Calculations (3 marks)

A 20% by volume solution of carbon dioxide in air is passed through a container holding 100 g of water at 25°C. The partial pressure of carbon dioxide in the air is 0.2 atm. Calculate the mass of carbon dioxide that will dissolve in the water.