A solution containing 1.22 g of a diprotic acid H2CH2O4 (malonic acid) was titrated with 45.5 mL of NaOH to reach the second equivalence
point. What is the concentration of the NaOH solution? (MW_malonic
acid = 104.06 g/mol)

0.515 M

Explanation:

The reaction that takes place is:

First we convert 1.22 g of malonic acid into moles, using its molar mass:

Then we convert 0.01172 malonic acid moles into NaOH moles, using the stoichiometric coefficients of the balanced reaction:

Finally we calculate the concentration of the NaOH solution, using the number of moles and given volume:

Converting 45.5 mL ⇒ 45.5/1000 = 0.0455 L

the answer to your question is c

when the volume of gas is   changed from   717.73 ml   to 852 ml   the temperature will   change   from 315   c to 452   c

    calculation

this is calculated using the charles law formula

that is,   v1/t1 = v2/t2

          v1=?

        t1 = 315 c   into   kelvin = 315 +273 = 588 k

        v2 = 852   ml

        t2 = 425c + 273 =698 k

make v1   the subject of the formula ( by   multiplying both side by t1)

  v1=( v2 xt1) / t2

v1= (852 ml   x 588 k)/ 698 k= 717.73 ml