# Problem: The air in an inflated balloon (defined as the system) is warmed over a toaster and absorbs 125 J of heat. As it expands, it does 78 kJ of work. What is the change in internal energy for the system?

###### FREE Expert Solution

$\overline{){\mathbf{∆}}{\mathbf{E}}{\mathbf{=}}{\mathbf{q}}{\mathbf{+}}{\mathbf{w}}}$

where w is work; and q is the heat release or absorb

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###### Problem Details
The air in an inflated balloon (defined as the system) is warmed over a toaster and absorbs 125 J of heat. As it expands, it does 78 kJ of work. What is the change in internal energy for the system?