Answer to Question #102894 in General Chemistry for conspire

Question

The PBS protocol above says to adjust pH to 7.4 with HCl. What does this imply on the pH of 10x PBS before adjusting the pH, would it be greater or smaller than 7.4?

Answer 1

 PBS stands for phosphate buffered saline which is used in biological research. It is a salty solution that contains sodium chloride, sodium phosphate, potassium chloride and potassium phosphate. The buffer helps maintain a constant pH. HCl is a strong base and tends to lower pH. If the PBS protocol is to adjust pH to 7.4 with HCl, this implies that the pH of the 10X PBS was greater than 7.4.