A mixture of krypton and oxygen gas is compressed from a volume of 100.0 L to a volume of 71.0 L, while the pressure is held constant at 19.0 atm. Calculate the work done on the gas mixture. 

The electron in a hydrogen atom is known to be in a state with magnetic quantum number m = 1.  What is the smallest possible value of the principal quantum number n of the state?   

When HF dissolves in water, the species present in water are H+, F-, and HF. So HF is

An arctic weather balloon is filled with 49.2 L of helium gas inside a prep shed. The temperature inside the shed is 11.0 C. The balloon is then taken outside, where the temperature is -31.0 C. Calculate the new volume of the balloon. Assume helium gas is an ideal gas and the pressure on the balloon stays constant. T (in K) = T (in C) + 273.15. 

A chemical reaction takes place inside a flask submerged in a water bath. The water bath contains 7.40 g of water at 20.3 C. During the reaction, 145 J of heat flows out of the bath and into the flask. The heat capacity of water is 4.18 J/(gK). Calculate the new temperature of the water bath.  q=cmT. 

Measurements show that the energy of a mixture of gaseous reactants increases by 264 KJ during a certain chemical reaction, which is carried out at a constant pressure. Furthermore, by carefully monitoring the volume change it is determined that 82 KJ of work is done on the mixture during the reaction. Calculate the change in enthalpy of the gas mixture during the reaction. 

This energy diagram shows the allowed energy levels of an electron in an atom: Which transition causes the emission line at the shortest wavelength?

During the Middle Ages, the Roman Catholic Church spread across Western Europe. This provided stability and hope for many. Therefore, the Church is seen as the source of unification of Western Europe.

For 3d orbital, the angular momentum quantum number = ?

Eastern Roman Empire centered around the trade center of Constantinople. Historians will later call Eastern Rome __.