In the equation for the ideal gas law, PV = nRT, which of the following sets of variables are typically considered unknowns that can be solved for if the other variables are provided?

• A. Pressure (P), Volume (V), Temperature (T), and Moles (n)
• B. Only Pressure (P) and Volume (V)
• C. Only Temperature (T) and Moles (n)
• D. Only the gas constant (R)

Answer: (A)

Verified step by step guidance

1. Understand the ideal gas law equation: \(P V = n R T\), where \(P\) is pressure, \(V\) is volume, \(n\) is the number of moles, \(R\) is the gas constant, and \(T\) is temperature.
2. Recognize that \(R\) (the gas constant) is a known constant value and does not change for a given problem, so it is not typically an unknown variable to solve for.
3. Identify that the variables \(P\), \(V\), \(n\), and \(T\) are the quantities that can vary and are often unknowns in problems involving gases.
4. Note that if any three of these variables (\(P\), \(V\), \(n\), \(T\)) are known, the fourth can be calculated by rearranging the ideal gas law equation.
5. Conclude that the typical unknowns to solve for in the ideal gas law are Pressure (\(P\)), Volume (\(V\)), Temperature (\(T\)), and Moles (\(n\)), while \(R\) remains constant.