Ch 3 pH

Question 1

Acid

Answer 1

a substance that increases the hydrogen ion concentration of a solution

<7 ph

A molecule (or group of molecules) either release hydrogen ions (a hydrogen that’s positively charged/has lost an electron), or take up hydroxide ions (has picked up an extra electron)

Question 2

Base

Answer 2

a substance that reduces the hydrogen ion concentration of a solution

> 7 ph

Either releases hydroxide ions or takes up hydrogen ions

Question 3

pH

Answer 3

a scale, 0-14, to measure if a solution is basic or acidic (can only be applied to aqueous solutions)

Solution is neutral when hydroxide and hydrogen ions are balanced

Question 4

-log(H+)

Answer 4

the greater the hydrogen ion (H+) concentration/more acidic something is, the lower the number of ph (inversely proportional)

Question 5

Explain how buffers work

Answer 5

Mixture of a weak acid and its base, neutralizes extreme acids or bases. Resists ph change (not necessarily going back to neutral)

They can accept an excess of hydrogen or hydroxide ions

Question 6

Explain why buffers are important to living organisms

Answer 6

Even a slight change in ph can be harmful because the chemical processes of the cell are very sensitive to the concentrations of hydrogen and hydroxide ions