Chem Acids and Bases
Which of the following does not describe an acid?
1. Acids react with bases. 2. Acids donate hydroxide ions in water. 3. Acids taste sour. 4. Acids donate hydrogen ions in water.
Consider the reaction HNO3 + H2O → H3O + + NO−3 Which is acting as a base? 1. H2O 2. No substance in this equation is acting as a base. 3. H3O + 4. HNO3
1. H2O
The most acidic solution is the one with 1. MOH− = 10−9 2. MOH− = 10−6 3. MOH− = 10−7 4. MOH− = 10−8 5. MOH− = 10−5
1. MOH− = 10−9 The Higher the number next to e is, the more acidic it will be.
If the pH changes from 12 to 11, the OH− concentration would 1. decrease. 2. increase. 3. Neither of these
1. decrease.
In a beaker containing 100 mL of water, equal moles of HCl and Ca(OH)2 are mixed. The resulting solution contains mainly which of the following? [HINT: Balance the equation!] 1. water, Cl−, Ca2+, and OH− ions 2. water and CaCl2 3. water and Cl−, Ca2+, and H+ ions 4. water, HCl and Ca(OH)2 5. water and Cl− and Ca2+ ions 6. water and H+, Cl−, Ca2+, and OH− ions
1. water, Cl−, Ca2+, and OH− ions
Which chemical equation shows the dissociation of magnesium hydroxide?? 1. Mg(OH)2 → Mg2+ + 2 H2O 2. Mg(OH)2 → Mg2+ + 2 OH− 3. Mg(OH)3 → Mg3+ + 3 OH− 4. MgOH → Mg2+ + OH2−
2. Mg(OH)2 → Mg2+ + 2 OH−
A sample of pure water is neutral because it contains 1. only H2O molecules. 2. some hydroxide ions. 3. equal amounts of hydroxide and hydronium ions. 4. some hydronium ions.
3. equal amounts of hydroxide and hydronium ions.
According to the Arrhenius Theory, an acid produces ? and a base produces ? . 1. electrons; protons 2. hydroxide ions (OH−); hydrogen ions (H+) 3. protons; electrons 4. hydrogen ions (H+); hydroxide ions (OH−)
4. hydrogen ions (H+); hydroxide ions (OH−) H is Hydrogen and OH is for Hydroxide
Arrhenius acids are 1. substances that cause the pH of a solution to increase. 2. substances that produce hydroxide ions in solution. 3. substances that produce hydrogen atoms in solution. 4. substances that produce hydronium ions in aqueous solution.
4. substances that produce hydronium ions in aqueous solution. (They Produce Ions)
What is [OH−] when [H3O +] = 8.2×10−5 M? 1. 1.0 × 10−7 M 2. 1.2 × 10−10 M 3. 1.2 × 10−4 M 4. 6.3 × 10−9 M 5. 8.2 × 10−5 M How would you solve this?
Answer: 2. 1.2 × 10−10 M Steps: - use -log10(8.2e-5) - Subtract sum by 14 and change the sign -result will be the used next to e
Complete the following statement. A pH value of −1.5 1. indicates an H+ concentration of −0.0316M. 2. indicates an H+ concentration of 31.6 M. 3. indicates an H+ concentration of 0.0316M. 4. is impossible because pH cannot be negative. 5. indicates an H+ concentration of −0.0176M. 6. indicates an H+ concentration of 0.176M.
Answer: 2. indicates an H+ concentration of 31.6 M. How to get this: - Use the equation 10^(Negative poh or ph) - So in this case: 10^(1.5)
A solution has [H+] = 3.9 × 10−4 M. Find the pH of this solution. 1. neutral 2. 10.59 3. 3.41 4. −3.40 5. 4.41
Answer: 3. 3.41 How to get it: - Since you're given Molarity, and you are trying to find pH, use -log10(3.9 × 10e-4) to get your answer
A typical glass of orange juice will have a pH of 3.50. This corresponds to 1. [H3O+] of 8.5 × 10−7 M; [OH−] of 5.5 ×10−7 M . 2. [H3O+] of 1.6 × 10−3 M; [OH−] of 6.3 ×10−12 M . 3. [H3O+] of 2.3 × 10−5 M; [OH−] of 4.3 ×10−10 M . 4. [H3O+] of 3.0 × 10−8 M; [OH−] of 3.3 ×10−7 M . 5. [H3O+] of 3.2 × 10−4 M; [OH−] of 3.2 ×10−11 M .
Answer: 5. [H3O+] of 3.2 × 10−4 M; [OH−] of 3.2 ×10−11 M . How do you get it?: It's simple, you have the pH and you can easily find the the Molarity by using 10^(Negative pH or poh) to get your answer.
A solution with a higher pH is more acidic. True or False?
False
What property would be possessed by BOTH acids AND bases? -
They Conduct electricity