HP 33s Scientific HL P z, Zl T, 4Solving Equations, Example Solving the Ideal Gas Law Equation

Example: Solving the Ideal Gas Law Equation.

The Ideal Gas Law describes the relationship between pressure, volume, temperature, and the amount (moles) of an ideal gas:

P ⋅ V = N ⋅ R ⋅ T

where P is pressure (in atmospheres or N/m2), V is volume (in liters), N is the number of moles of gas, R is the universal gas constant (0.0821 liter–atm/mole–K or 8.314 J/mole–K), and T is temperature (Kelvins: K=°C + 273.1).

Enter the equation:
Keys:	Display:	Description:
HLP z	º¾	Selects Equation mode
		and starts the equation.
LV d	
LN z	
LR zLT	º#/ºº!¾
‘	º#/ºº!	Terminates and displays
		the equation.
	/	Checksum and length.
	/

A 2–liter bottle contains 0.005 moles of carbon dioxide gas at 24°C. Assuming that the gas behaves as an ideal gas, calculate its pressure. Since Equation mode is turned on and the desired equation is already in the display, you can start solving for P:

Keys:	Display:	Description:
P	#@	Solves for P; prompts for
	value	V.
2 g	@	Stores 2 in V; prompts for
	value	N.
.005 g	@	Stores .005 in N;
	value	prompts for R.
.0821 g	!@	Stores .0821 in R;
	value	prompts for T.
￿ 24 ‘273.1›	!@	Calculates T (Kelvins).
	 )

7–4Solving Equations