A mixture of helium and argon gas is compressed from a volume of 100.0 L to a volume of 99.0 L, while the pressure is held constant at 39.0 atm. Calculate the work done on the gas mixture. Be sure your answer has the correct sign (positive or negative) and the correct number of significant digits.

A 2.63 g sample of a substance suspected of being pure gold is warmed to 72.8 degrees Celsius and submerged into 15.5 g of water initially at 24.5 degrees Celsius. The final temperature of the mixture is 27.0 degrees Celsius. What is the specific heat capacity of the unknown substance? Express your answer using to significant figures.

A piece of unknown metal with a mass of 23.78 g is heated in boiling water to 97.4°C and then dropped into a coffee cup calorimeter containing 72.71 g of water at 13.65°C. When thermal equilibrium is reached, the final temperature is 24.79°C. Calculate the specific heat capacity of the unknown metal. The specific heat of water is 4.184 J/g/°C.   Round your answer to 2 decimal places.

A chemical reaction takes place inside a flask submerged in a water bath. The water bath contains 9.80kg of water at 27.4°C . During the reaction 140.kJ of heat flows out of the flask and into the bath. Calculate the new temperature of the water bath. You can assume the specific heat capacity of water under these conditions is 4.18J·g−1·K−1 . Be sure your answer has the correct number of significant digits.