Does 2NO2 converting to O2 + N2 follow the law of conservation of mass

One of the cell membrane's functions is to protect the cell keep wastes in the cell create new cells keep light out of the cell

Calculate the molarity of 48.0 ml of 6.00 m h2so4 diluted to 0.250 l .

A50.0 ml sample of gas at 20.0 atm of pressure is compressed to 40.0 atm of pressure at constant temperature. what is the new volume? 0.0100 ml 0.325 ml 25.0 ml 100. ml