An astronaut in a spacesuit on a spacewalk is a completely sealed system, with no matter lost or gained. In principle, the energy the astronaut uses will result in a decrease in mass. Suppose on a gentle spacewalk his metabolic power plus the power of the suit is 340 W. What is the change in mass, in kg, on a 1.0 hour spacewalk?

Acylinder with a movable piston contains 11.7 moles of a monatomic ideal gas at a pressure of 1.32×10^5 pa. the gas is initially at a temperature of 300 k. an electric heater adds 43200 j of energy into the gas while the piston moves in such a way that the pressure remains constant. cp=20.79 j k^−1 mol^−1 for a monatomic ideal gas, and that the number of gas molecules is equal to avogadro's number (6.022×10^23) times the number of moles of the gas. (a) what is the temperature of the gas after the energy is added? (b) what is the change in volume of the gas? (c) how much work is done by the gas during this process?