The mixing of which pair of reactants will result in a precipitation reaction? A. AsI(aq) + NaOH(aq)
B. NaNO3(aq) + NH4Cl(aq)
C. K2SO4(aq) + Ba (NO3)2(aq)
D. HCl(aq) + Ca(OH)2(aq)
E. None of the above.

When a chemist collects hydrogen gas over water, she ends up with a mixture of hydrogen and water vapor in her collecting bottle. if the pressure in the collecting bottle is 97.1 kilopascals and the vapor pressure of the water is 3.2 kilopascals, what is the partial pressure of the hydrogen?