Question

calculate the change in internal energy, in kj, for a system that absorbs 4.52×10⁴ j of heat and has 8.61×10⁴ j of work done by the surroundings. report your answer to the first place after the decimal point.

Explanation:

Step1: Recall the first law of thermodynamics formula

The first law of thermodynamics is \(\Delta U = Q+W\), where \(\Delta U\) is the change in internal energy, \(Q\) is the heat absorbed by the system, and \(W\) is the work done on the system. Given \(Q = 4.5\times10^{4}\space J\) and \(W=8.6\times 10^{4}\space J\)

Step2: Calculate \(\Delta U\)

Substitute the values into the formula: \(\Delta U=(4.5\times 10^{4}+8.6\times 10^{4})\space J\)

$$
LATEXBLOCK0
$$

Convert \(J\) to \(kJ\): Since \(1\space kJ = 10^{3}\space J\), then \(\Delta U=\frac{13.1\times 10^{4}}{10^{3}}\space kJ\)

$$ \Delta U = 131.0\space kJ $$

Answer:

\(131.0\space kJ\)