Question

Liquid nitrogen, which has a boiling point of 77 K, is commonly used to cool substances to low temperatures.
How much energy must be removed from
1.4 kg of gaseous nitrogen at 77 K for it to completely liquefy? Assume the latent heat of liquid nitrogen is 2.01 × 105 J/kg.
Answer in units of J

Answer 1

1.4 kg x 2.01 J/kg = ?

Answer 2

281400

Answer 3

Not on my calculator. 1.4 x 2.01 = 2.81 J. right?

Answer 4

it's 2.01*10^5