User Task - Formula Library

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1. Solve the following equations:
a) 4x2-13x+3=0
b) 5x-1=-6x^2

Select the "Quadratic Formula" from the menu.

Arrange the equation in standard form (ax2+bx+c=0), and enter the according parameters.

Press "Enter" to see the answer.

2. The ideal gas law is used in chemistry to do calculations for gasses like oxygen (O2), carbon-dioxide (CO2), etc. It is expressed as the equation

P V = n R T,

P is the pressure of the gas
V is the volume (how much space) the gas takes up
n is how many molecules of the gas there are
R is a constant equal to 0.0821 L atm/(mol K)
T is the temperature of the gas, in Kelvin. The temperature in Kelvin is equal to 273.15 plus the temperature in Celcius

A sample of gas is known to have these values:

volume: 0.850 L
mass: 1.090 g
pressure: 0.982 atm
temperature: 25 degrees celcius

How many molecules of the gas are there?

Select "Custom Formula" from the menu.

Enter "P*V=N*R*T" manually using the keyboard. (This text interface is not implemented.)

Enter the following parameters, leaving the unknown N blank:

V = 850
P = 0.982
T = 298.15 (because 25.0oC + 273.15 = 298.15 K )

Press "Enter" to see the answer.

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