Question 1: Explain the term 'atmospheric pollutant' and give two examples of common pollutants found in the atmosphere.

Answer: An atmospheric pollutant is a substance introduced into the atmosphere that has harmful effects on living organisms or the environment; examples include carbon monoxide (CO) and nitrogen dioxide (NO2).

Question 2: Describe how the combustion of fossil fuels contributes to the formation of nitrogen oxides (NOx).

Answer: Fossil fuel combustion at high temperatures causes nitrogen and oxygen in the air to react, forming nitrogen oxides (NO and NO2), which are pollutants.

Question 1: Calculate the mass of sulphur dioxide (SO2) emitted if a factory releases 2000 cubic metres of exhaust gas containing 0.5% by volume of SO2. Assume the temperature is 25°C and pressure is 101 kPa. (Use molar volume = 24 dm³/mol)

Answer: Mass of SO2 = 2.5 kg

Question 2: A vehicle emits 0.8 grams of carbon monoxide (CO) per kilometre. How much CO is emitted after travelling 150 km?

Answer: 120 grams

Question 1: Describe a simple experiment to test for the presence of nitrogen dioxide (NO2) in the atmosphere. Include the safety precautions you should take.

Answer: Expose a piece of litmus paper to the atmosphere in a location suspected of NO2 presence; if NO2 is present, the paper will turn red. Wear safety goggles and avoid inhaling fumes, conducting tests in well-ventilated areas.

Question 1: In an urban area, measurements show that nitrogen dioxide (NO2) levels vary from 40 to 80 parts per billion (ppb) during the day. Explain what factors might cause these fluctuations and discuss the potential health implications.

Answer: Fluctuations are caused by traffic density, weather conditions, and industrial activity. Elevated NO2 levels can cause respiratory problems and contribute to acid rain.

Question 1: Describe how catalytic converters in vehicles help reduce nitrogen oxides (NOx) emissions and explain why this technology is important for environmental protection.

Answer: Catalytic converters use catalysts such as platinum, palladium, and rhodium to convert NOx into nitrogen and oxygen gases during exhaust emissions. This reduces air pollution, improves air quality, and helps meet environmental regulations.