Question

A sample of uranium absorbs 27.16 kJ of energy and changes temperature by 347.6 C. If 27.17 J/(1C * 1 mole) for uranium, the how many mole of U are in the sample?

Answer 1

Answer:

Q = 2.877 mole (4 sig. figs.)

Explanation:

Using Q = m·c·ΔT => m = Q/c·ΔT

Q = 27.16 Kj

c = 27.17 j/g·°C = 0.02717 Kj/g·°C

ΔT = 347.6 °C  

Q = 27.16 Kj/(0.02417j/mol·°C)(347.6°C) = 2.87.6869965 mol (calc. ans.)

= 2.877 mole (4 sig. figs.)