Acids/Bases/Buffers

Question 1

pH scale

Answer 1

a measurement of the concentration of hydrogen ion (H+), measure on the logarithmic scale

Question 2

Water

Answer 2

• neutral

- pH = 7 or [H+] = 10^-7 mol/Liter of hydrogen ions in a solution

Question 3

acidic compounds

Answer 3

a pH

Question 4

basic compounds

Answer 4

a pH > 7; lower concentration of H+ ions; release H+ ions when added to a solution

Question 5

buffers

Answer 5

• mixture of a weak acid and a weak base
• resist a change in pH, mixtures of a weak acid and a weak base
• have a range where they can act as a buffer

Question 6

Calculating a pH

Answer 6

• pH = -log[H+}
• concentration is measured in moles/Liter
• 1 mole = 6.022x10^23 atoms
• a pH of 7 means there are 10^-7 moles/L of Hydrogen ions in a solution

Question 7

Why are acids and bases important?

Answer 7

• when a solution has a very high or low pH it can be reactive and very corrosive (ability to dissolve a substance)
• Bleach and ammonia are a principle component of many products
• Hydrochloric acid is the main component of stomach acid

Question 8

Molarity

Answer 8

1 mole of molecules in 1 Liter solution of water = 1 mol/ 1 L of water

Question 9

1 mole

Answer 9

molecular weight of molecule

Question 10

Dilution

Answer 10

• Vi (initial volume) Mi (initial molarity) = Vf (final volume) Mf (final molarity)
• stock solutions are then diluted with water to make new solutions having a desired molarity

Question 11

stock solutions

Answer 11

solutions in concentrated forms

Question 12

solution

Answer 12

consists of solute dissolved in solvent