What is the density of carbon monoxide (CO) gas at standard temperature and pressure (STP)?

• A. 1.43 g/L
• B. 1.25 g/L
• C. 2.00 g/L
• D. 0.89 g/L

Answer: (A)

Verified step by step guidance

1. Recall that the density (\(d\)) of a gas can be calculated using the formula \(d = \frac{m}{V}\), where \(m\) is the mass of the gas and \(V\) is its volume.
2. At standard temperature and pressure (STP), one mole of any ideal gas occupies 22.4 liters. Use this fact to relate the molar mass of carbon monoxide to its volume at STP.
3. Calculate the molar mass of carbon monoxide (CO) by adding the atomic masses of carbon (C) and oxygen (O). The atomic mass of carbon is approximately 12.01 g/mol and oxygen is approximately 16.00 g/mol, so \(M_{CO} = 12.01 + 16.00\) g/mol.
4. Use the molar mass and molar volume at STP to find the density using the formula \(d = \frac{M}{V_m}\), where \(M\) is the molar mass and \(V_m\) is the molar volume (22.4 L at STP).
5. Substitute the values into the formula to get the density of CO gas at STP, ensuring units are consistent (grams for mass and liters for volume).