Acids & Bases Review

pH and pOH

100

What is the pH of a substance with a pOH of 12?

2

200

What is the pH of a substance with a concentration of 1.23 x 10^-4 mol/L of hydronium ions?

pH = 3.910

300

What is the pOH of a substance with [OH^-(aq)] of 2.34 x 10^-6 mol/L ?

5.631

400

What is the pH of a substance with [OH^-(aq)] of 6.7 x 10^-9 mol/L?

pH = 5.83

500

What is the concentration of hydroxide ions in a solution with a pH of 13.66 ?

0.46 mol/L 

OR 4.6 x 10^-1 mol/L

Acid-Base indicators

100

What colour is methyl violet at a pH of 1.0?

Yellow

200

What colour is thymolphthalein at a pH of 11.0?

Blue

300

What colour is phenol red at a pH of 7.2?

Orange

400

A substance turns: Bromocresol green --> yellow, Methyl orange --> orange, Orange IV --> yellow

Estimate the pH.

3.2-3.8

500

Thymol blue turns green, cresol red turns orange. Estimate the pH.

8.0-8.8

Acid and Base properties

100

A substance tastes sour and is mildly corrosive. The substance is a ______

(weak) acid

200

A substance has turned red litmus paper blue and doesn't react with metals. What kind of ions is it producing?

Hydroxide ions, OH^-(aq)

300

Is Mg(OH)₂(aq) a strong base? Justify your answer.

No. It is not soluble in water.

400

Name 2 properties to distinguish a strong base from a weak base.

- pH > 12 vs 7 < pH < 12

-High conductivity vs lower conductivity

-100% dissociation vs <50% dissociation

500

Name 2 properties to distinguish a strong acid from a weak acid.

-High conductivity vs lower conductivity

-Fast reaction vs slower reaction of metals

-pH < 2 vs  2 < pH < 7

Polyprotic and Monoprotic

100

What is a monoprotic acid? Give a definition and an example

An acid that can only react with water ONCE to produce a hydronium ion. 

200

What is a polyprotic acid?

An acid that can react with water twice to produce hydronium ions.

300

Demonstrate, with reactions, that CO₃^2-(aq) is a polyprotic base.

CO₃^2-(aq) + H₂O(l) --> OH^-(aq) + HCO₃^-(aq)

HCO₃^-(aq) + H₂O(l) --> OH^-(aq) + H₂CO₃(aq)

400

Is NH₃(aq) a polyprotic base?

No - it can only react with water once!

500

Is CH₃COOH(aq) a polyprotic acid?

No - it can only react with water once!

Modified Arrhenius Theory

100

HCl(aq) has a pH = 1

H⁺(aq) + H₂O(l) --> H₃O⁺(aq)

200

KOH(aq) has a pH = 13

KOH(aq) --> K⁺(aq) + OH^-(aq)

300

SO₃ turns blue litmus paper red

SO₃(aq) + 2H₂O(l) --> H₃O⁺(aq) + HSO₄^-(aq) 

400

Na₂CO₃(aq) turns phenolphthalein pink

CO₃^2-(aq) + H₂O(l) --> OH^-(aq) + HCO₃(aq)

500

KHSO₃(aq) turns methyl red red.

HSO₃^-(aq) + H₂O(l) --> H₃O⁺(aq) + SO₃^2-(aq)