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An atom contains a total of 52 electrons.  When the atom is in the ground state, how many different principal energy levels will contain electrons?

The pressure of 10 mL of a gas at constant temperature is changed from 4 atm to 2 atm.  The new volume of the gas is:

What is the specific heat capacity of a metal if it requires 169.6 J to change the temperature of 15.0 g of the metal from 25.00°C to 32.00°C?

What does a calorimeter constant represent?

According to the following reaction:2Al(s) + 3Cl2 (g) –> 2 AlCl3 (s)  ∆H=-1390.81 kJHow much heat is produced/required when 10.0g AlCl3 forms?

When a system performs work on the surroundings, the work is reported with a negative sign.

A gas absorbs 0.0 J of heat and then performs 15.8 J of work. The change in internal energy of the gas is

In a coffee cup calorimeter, 50.0mL of 0.1M AgNO3 and 50mL of 0.100 M HCl are mixed to yield the following reaction: Ag+ (aq) + Cl- (aq) –> AgCl(s) The two solutions were initially at 22.60 ° C, and the final temperature is 23.40 ° C. Calculate the heat that accompanies this reaction in KJ/mol of AgCl formed. Assume that the combined solution has a mass of 100.0g and a specific heat capacity of 4.18J/g ° C. (Hint: q=ms ∆ T;  ∆ H=q/mol) Answer: [BLANK-1]kJ/mol *Provide answer with correct sig. figs. and in the units indicated above.

If the chemical reaction is exergonic, the temperature of the water will decrease as energy is being transferred to the products.

A gas releases 45kJ of heat and does 29kJ of work. Calculate  ∆ E . Answer: [BLANK-1] kJ **Please give answer with correct sig.figs. and in the unit provided above.