A 70-liter tank of oxygen gas at 27 degree Celcius and 42.0 atm springs a leak overnight. when the tank was found in the morning, the pressure in the tank had dropped to 19.0 atm. If the tank originally held 119.4 moles of oxygen gas, how many moles of gas were left the next morning, assuming the temperature and volume of the rank stayed constant?

How air particles exert a pressure on the inside of the balloon

A3.37-mg sample of protein was chemically digested to convert its nitrogen into ammonia and then diluted to 100.0 ml. then 10.0 ml of this solution was placed in a 50-ml volumetric flask and treated with 5 ml of phenol solution plus 2 ml of sodium hypochlorite solution. the sample was diluted to 50.0 ml, and the absorbance at 625 nm was measured in a 1.00-cm cuvette and found to be 0.486. for reference, a standard solution was prepared from 10.0 mg of nh4cl (molar mass = 53.49 grams/mole) dissolved in 1.00 l of water. then 10.0 ml of this standard was placed in a 50-ml volumetric flask, treated in the same manner as the unknown, and the absorbance found to be 0.323. finally, a reagent blank was prepared using distilled water in place of unknown, it was treated in the same manner as the unknown, and the absorbance found to be 0.076. calculate the weight percent of nitrogen in the protein.

In a chemical reaction at equilibrium, the rate of the forward reaction the rate of the reverse reaction. if the rate of the forward reaction more products are formed.