Question

1a. Identify two ways in which a titration curve for a strong acid/strong base differs from that of a strong acid/weak base or weak acid/strong base.

1b. Why it is important for the pH of the stomach to be in the low range? Ideally, what effect does stomach pH have on the pH of blood?

1c. Describe the factors responsible for the deviation of the behavior of real gases from that of an ideal gas.

1d. A gas of unknown identity diffuses at a rate of 95.5 mL/s in a diffusion apparatus in which carbon dioxide diffuses at the rate of 110 mL/s. Calculate the molecular mass of the unknown gas.

1e. Heavy water, D₂O (molar mass = 20.03g mol–1), can be separated from ordinary water, H₂O (molar mass = 18.01), as a result of the difference in the relative rates of diffusion of the molecules in the gas phase. Calculate the relative rates of diffusion of H₂O and D₂O.

Answer 1

Ans 1(a) The major difference is the pH at the equivalence point. In case of strong acid vs strong base, the pH at equivalence point is 7. In case of strong acid vs weak base ,the pH at equivalence point is less than 7. In case of strong base vs weak acid ,the pH at equivalence point is greater than 7...The shape of titration curve is nearly same in all cases..

Ans 1(b) Actually low pH means slightly acidic which helps us in the digestion of food .The pH of blood be maintained at a pH of 7.4. So, the regulation on the pH of stomach will help in regulating this value of pH of blood.

Ans 1(c) For a gas to be ideal it has to follow these two two assumptions :-1)The volume occupied by the gas molecules is negligibly small as compared to the volume occupied by the gas. The forces of attraction between gas molecules are negligible..So,gases deviate from these two assumptions ...

Ans 1(d)