Final answer:
At RTP, 1 mole of gas occupies 22.4 dm³. To find the moles of SO₂ in 1.2 dm³, divide the volume by the molar volume, which gives approximately 0.054 moles. The correct answer is A) 0.054 moles.
Step-by-step explanation:
To determine how many moles of sulfur dioxide (SO₂) are present in 1.2 dm³ at RTP, we use the molar volume of a gas at room temperature and pressure. RTP is generally considered to be 0°C (273 K) and 1 atmosphere. At RTP, one mole of any ideal gas occupies 22.4 dm³. Therefore, to find the moles of SO₂ in 1.2 dm³, we use the following calculation:
moles of SO₂ = volume of SO₂ (dm³) / molar volume at RTP (dm³/mol)
moles of SO₂ = 1.2 dm³ / 22.4 dm³/mol
moles of SO₂ = 0.05357 mol
When rounded to two decimal places, this value is approximately 0.054 moles.
So, the correct answer is A) 0.054 moles.