Calculate the decrease in temperature (in Celsius) when 2.00L at 21.0*C is compressed to 1.00.

Decrease in temperature is - 126.0°C

Explanation:

Using Charles law we can set up the equation as,

V₁/T₁ = V₂/T₂

(2.00 L) / 294.0 K) = (1.00 L) / (x)

cross multiply to get:

2x = 294

2x/2 = 294/2

x = 147.0 K

Now kelvin is converted into Celsius by subtracting 273 from 147 as,

147 - 273 = - 126°C