Which corresponds to a pressure of 1.23 atm? ?

Atmospheric pressure, sometimes also called barometric pressure, is the pressure exerted by the weight of air in the atmosphere of Earth (or that of another planet)

1 atm is equivalent to = 101325 Pa

= 760 mmHg

= 760 torr

= 1.01325 bar

So 1.23 atm is equal to

= 124629.8 Pa

= 934.8 mmHg

= 934.8 torr

= 1.2462 bar

the answer is either b or c

nacl is added to the aqueous of what? ? in order to get a proper answer you have to specify the exact composition of the aqueous solution.