Three 15.0 mL acid samples – 0.10 M HA, 0.10 M HB, and 0.10 M H2C – are all titrated with 0.100 M NaOH. If HA is a weak acid, HB is a strong acid, and H2C is a diprotic acid, which statement is true of all three titrations?

a. All three titrations have the same final pH.

b. All three titrations require the same volume of NaOH to reach the first equivalence point.

c. All three titrations have the same pH at the first equivalence point.

d. All three titrations have the same initial pH.

the grams   of   barium that   are in   2.3 x 10^23   atoms of barium   is   52.4 g (answer c)

    calculation

mass = moles   of ba   x molar   mass of ba

  molar mass of ba from periodic table=   137.3 g/mol

  use the   avogadro's law   constant   to   calculate the moles of barium

  that   is     1 mole =   6.02   x 10^23 atoms

                    ? moles = 2.3 x 10^23   atoms

by cross   multiplication

=(1 mole   x 2.3x 10^23 atoms)   / 6.02   x10^23 atoms)=   0.382   moles

mass   is therefore = 137.3   g/mol x 0.382 mol = 52.4 ( answer c)

explanation:

answer seismograph;

you need to stop taking that class