Acids and Bases

What are some examples of acids and bases in cleaning?

Hydrochloric acid: household cleaners and swimming pool maintenance Sodium and potassium hydroxides: manufacturer of soaps, detergents, drain cleaners Sodium hypochlorite: bleach, disinfectant Ammonia: window and household cleaner

Acids have low pH and high pOH.

True.

Acids react with carbonate or bicarbonate compounds to form CO2, H20, and a salt.

True.

Bases have high pH and low pOH.

True.

Bases react with carbon dioxide to form carbonate.

True.

Bases react with soluble metal salt to form insoluble metal hydroxide.

True.

What is a base?

a substance that reduces the H+ concentration of a solution or increases the OH- concentration.

What is neutralization?

acid + base = salt + water

What are the four pH equations?

pH = -log[H3O+] pOH = -log[OH-] [H3O+] = 10^-pH [OH-] = 10^-pOH

What are the physical and chemical properties of acids?

-sour taste -turn blue litmus paper red -turn methyl orange solution red -react with carbonates and bicarbonates -neutralized by bases -react with metals

What are the physical and chemical properties of bases?

-taste bitter -slippery -turn red litmus paper blue -turn colorless phenolphthalein pink -neutralize acids -may react with some metal salts -react with carbon dioxide

What is the hydronium ion concentration in pure water?

10^-7, or 0.0000001

Which substances are most likely acids? Check all that apply. 1. CH4 2. HI 3. NH3 4. HNO3 5. NaCl

2. HI 4. HNO3

What does acid form when it reacts with metal?

A salt and hydrogen gas.

What is an acid?

A substance that increases the concentration of H+ ions in a solution.

Which of these substances has the lowest pH? A. 0.5 M HBr, pOH = 13.5 B. 0.05 M HCl, pOH = 12.7 C. 0.005 M KOH, pOH = 2.3

A. 0.5 M HBr, pOH = 13.5

Based on the definition of logarithms, what is the difference in hydrogen ion concentration between a substance with a pH of 2 and a substance with a pH of 3? A. A substance with a pH of 2 has a 10 times higher concentration of H+ than a substance with a pH of 3. B. A substance with a pH of 3 has a 10 times higher concentration of H+ than a substance with a pH of 2. C. A substance with a pH of 2 has a 100 times higher concentration of H+ ions than a substance with a pH of 3. D. A substance with a pH of 3 has a 100 times higher concentration of H+ ions than a substance with a pH of 2.

A. A substance with a pH of 2 has a 10 times higher concentration of H+ than a substance with a pH of 3.

HBr + KOH → KBr + H2O In this reaction, the acid is A. HBr. B. KOH. C. KBr. D. H2O.

A. HBr.

Which statement best describes the pH of pure water? A. It is neutral because the concentration of hydronium ions equals that of hydroxide ions. B. It is neutral because the pure liquid contains neither hydronium ions nor hydroxide ions. C. It is acidic because it has a hydronium ion concentration of 1.0 x 10^-7 M. D. It is basic because it has a hydroxide ion concentration of 1.0 x 10^-7 M.

A. It is neutral because the concentration of hydronium ions equals that of hydroxide ions.

Identify the base in this acid-base reaction: NaOH + HCl → NaCl + H2O A. NaOH B. HCl C. NaCl D. H2O

A. NaOH

The pH of a solution is 2.0. Which statement is correct? Useful formulas: H3O+ = 10^-pH, OH- = 10^-pOH, pH + pOH = 14, H3O+ x OH- = 10^-14 A. The pOH of the solution is 12.0. B. The concentration of OH- ions is 1.0 x 10^-2 M. C. The concentration of H3O+ ions is 100.0 M. D. The pOH of the solution is 16.0.

A. The pOH of the solution is 12.0.

H2SO4 is added to a large beaker of water. How is the solution different from the original water? A. The solution turns blue litmus to red. B. The solution turns phenolphthalein pink. C. The solution has fewer hydrogen ions. D. The solution has more hydroxide ions.

A. The solution turns blue litmus to red.

Which of these acids occurs naturally in the body and performs important regulatory functions? A. carbonic acid B. acetic acid C. magnesium hydroxide D. sodium hydroxide

A. carbonic acid

When does phenolphthalein turn pink? A. in the presence of a base B. in the presence of an acid C. when it is in a neutral solution D. when it is reacting with a metal

A. in the presence of a base

Which of these substances is the most basic (alkaline)? A. solution A, pOH = 1.5 B. solution B, pOH = 7.0 C. solution C, pOH = 13.5

A. solution A, pOH = 1.5

Where are bases (alkaline) on the pH scale?

Above 7.

Limestone is made of calcium carbonate, CaCO3. Would you use an acid or a base to test a rock sample to determine whether it contains calcium carbonate?

Acid.

What is a salt?

An ionic compound formed by combining an acid and a base.

What are some examples of acids and bases in medicine and health?

Antacids Magnesium hydroxide: antiperspirant and laxatives Hydrochloric acid: stabilizer for medications Carbonic acid: regulator for blood

The pOH of a solution is 10.75. What is the concentration of OH- ions in the solution? Use OH- = 10^-pOH. A. 3.162 x 10^-108 M B. 1.778 x 10^-11 M C. 1.075 x 10^2 M D. 5.623 x 10^10 M

B. 1.778 x 10^-11 M

What is the equilibrium constant of pure water at 25°C? A. 10^14 B. 10^-14 C. 10^-7 D. 10^7

B. 10^-14

Calcite (the main mineral in limestone) is made of calcium carbonate (CaCO3). Dolomite, a related mineral, is made of magnesium carbonate (MgCO3). What happens if a geologist drips a small amount of vinegar (acetic acid) onto a sample of dolomite? A. There is no way to predict what will happen. B. Fizzing will occur because carbon dioxide is produced. C. No reaction will occur because dolomite contains no calcium.

B. Fizzing will occur because carbon dioxide is produced.

Which description correctly characterizes the acidity or basicity of a solution? A. The higher the pH is, the more the hydroxide ion concentration decreases and the more acidic the solution becomes. B. The higher the pH is, the more the hydroxide ion concentration increases and the more basic the solution becomes. C. The lower the pH is, the more the hydronium ion concentration decreases and the more acidic the solution becomes. D. The lower the pH is, the more the hydronium ion concentration increases and the more basic the solution becomes.

B. The higher the pH is, the more the hydroxide ion concentration increases and the more basic the solution becomes.

Which statement about the self-ionization of water is correct? A. Two water molecules interact to form a water molecule and a hydroxide ion. B. Two water molecules interact to form a hydronium ion and a hydroxide ion. C. Two water molecules interact to form two hydronium ions. D. Two water molecules interact to form two hydroxide ions.

B. Two water molecules interact to form a hydronium ion and a hydroxide ion.

A solution containing HCl would likely have A. a high pH and a low pOH. B. a low pH and a high pOH. C. a high pH and a high pOH. D. a low pH and a low pOH.

B. a low pH and a high pOH.

Which compound plays an important role in leather processing and electroplating? A. nitric acid B. hydrochloric acid C. ammonia D. magnesium hydroxide

B. hydrochloric acid

Which pair of substances would most likely result in the production of a solid when reacting with a base? A. litmus and phenolphthalein B. soluble metal salt and carbon dioxide C. acids and water D. hydrogen ions and soaps

B. soluble metal salt and carbon dioxide

A student crushes some calcium supplement tablets and dissolves them in water. The resulting solution feels slippery and has a slightly bitter taste. Are the supplement tablets most likely to be acids or bases?

Bases.

Where are acids on the pH scale?

Below 7.

What are some examples of acids in foods?

Benzoic acid: preservative Carbonic acid: carbonated drinks Acetic acid: vinegar Tartaric acid: soft drinks, tartness Citric acid: fruits, preservatives, tartness

Which statement would indicate the presence of an acid? A. It tastes bitter. B. It does not react with active metals. C. It reacts with active metals to form a gas. D. It does not change the color of litmus paper

C. It reacts with active metals to form a gas.

Which describes an alkaline solution? A. pH less than 7 B. pH equal to 7 C. basic D. acidic

C. basic

What is a base used in toothpaste? A. sorbitol B. carrageenan C. magnesium hydroxide D. sodium lauryl sulfate

C. magnesium hydroxide

Which pair of substances would most likely result in the production of a gas when reacting with an acid? A. litmus and methyl orange B. base and salt C. metal and carbonate D. carbon dioxide and water

C. metal and carbonate

What is sulfuric acid used for?

Car batteries and used in acid rain.

What is the pH of a solution with [H+] = 1.25 x 10^-10 M? Use pH = -log[H3O+]. A. -10.1 B. -9.90 C. 7.90 D. 9.90

D. 9.90

A substance with a high pOH would likely have which of the following? A. A low [H+ ] and a high pH B. A low [OH- ] and a high pH C. A high [OH- ] and a low pH D. A high [H+ ] and a low pH

D. A high [H+ ] and a low pH

Which of the following best defines an acid? A. An acid has a pH of 7. B. An acid has hydroxide ions. C. An acid has fewer positive ions in solution. D. An acid has more hydrogen ions in solution.

D. An acid has more hydrogen ions in solution.

Look at the reaction below. H2SO4(aq) + Mg(s) → MgSO4(aq) + H2(g) Which substance is the acid in the reaction? A. Mg(s) B. H2(g) C. MgSO4(aq) D. H2SO4(aq)

D. H2SO4(aq)

Which is a characteristic of a strong base? A. It turns pink phenolphthalein colorless. B. It turns blue litmus paper red. C. It releases H+ ions into a solution. D. It removes H+ ions from solution.

D. It removes H+ ions from solution.

A substance with a high [H+ ] would likely have which additional characteristics? A. a high [OH- ] and a high pOH B. a low [OH- ] and a high pOH C. a high [OH- ] and a low pOH D. a low [OH- ] and a low pOH

D. a low [OH- ] and a low pOH

How can the pH of a solution be calculated if the pOH is known? A. by taking the negative logarithm of pOH B. by adding the pOH to 14 C. by raising 10 to the power of -pOH D. by subtracting the pOH from 14

D. by subtracting the pOH from 14

The reaction below demonstrates which characteristic of a base? CuSO4(aq) + 2NaOH(aq) → Cu(OH)2(s) + Na2SO4(aq) A. the ability of bases to release sodium ions into solution B. the ability of bases to release hydrogen ions into solution C. the ability of a base to react with carbonate or bicarbonate D. the ability of a base to react with a soluble metal salt

D. the ability of a base to react with a soluble metal salt

Which of these correctly defines the pOH of a solution? A. the log of the hydronium ion concentration B. the negative log of the hydronium ion concentration C. the log of the hydroxide ion concentration D. the negative log of the hydroxide ion concentration

D. the negative log of the hydroxide ion concentration

What foods is oxalic acid found in?

Potatoes and rhubarb.

What is acetic acid used for?

Vinegar and aspirins.

How are acids normally written?

With the H first.