Question

1.)The most common approach to control paper acidity is to include calcium carbonate (chalk) in the paper mix. As the paper is produced, some of the calcium carbonate reacts with the acid released by the lignin. Describe how this creates a buffer system, making sure to include the name of carbonate’s conjugate acid.

2.)The conjugate acid of carbonate also participates in a buffer system with carbonic acid, which keeps the pH of blood at 7.4. Do you expect the buffer created in the paper production to have a higher or lower pH than blood? Explain your reasoning.

Answer 1

CaCO_3 + 2 HCl rightarrow H_2CO_3 + CaCl_2 H_2CO_3 Equilibrium H^+ + HCO_3^- CaCO_3 is salt react with acid gives acid and CaCl_2 Carbonate acid (H_2CO_3) is a weak acid so it carboxy ionized which maintain pH of solution. In blood H_2CO_3 Equilibrium H^+ + HCO_3^- Carbonate buffer mechanism pH of blood is 7.4, actually blood is a syatem in which pH up and do not occurs with time by which carbonate buffer control phsy contain dissociation in forward direction and backward direction. But paper not a system it is a pulp of paper so there will no use of buffer system once carbonate form it decompose to gives equilibrium so H^+ concentration increases which lead to decreases in pH (acidic pH) so paper pulp has acidic pH lower than blood pH because blood pH is slightly basic.