Question

What is the pH of a solution prepared by dissolving 2.1 g of HCl in water to make 340. mL of solution?

when i did this i ended up getting 2.772, however its incorrect..

I also need help with these :(

complete and balance the equations

ZnCO3(s)+HI(aq)→

Zn(s)+HCl(aq)→

HCl(aq)+NaHCO3(s)→

Answer 1

concentration of HCl = w/mwt*1000/V

                      = (2.1/36.5)*(1000/340)

                      = 0.17 M

   pH = -log(H3O+) = -log0.17 = 0.77

ZnCO3(s)+ 2HI(aq) → ZnI2(aq) + CO2(g) + H2O(l)

Zn(s)+ 2HCl(aq) → H2(g) + ZnCl2(aq)

HCl(aq) + NaHCO3(s) → NaCl(aq) + CO2(g) + H2O(l)