ARRHENIUS ACIDS AND BASES
Which substance below is an Arrhenius Acid ?
a) HBr b) NaBr
c) NaOH d) NH3
a) HBr
Arrhenius acids produce hydrogen ions (H+) ions when dissolved in water: HBr (aq)→ H+(aq) + Br-(aq)
Which type of reaction occurs when an Arrhenius acid reacts with an Arrhenius base to form a salt and water?
a) combustion b) decomposition
c) neutralization d) saponification
c) neutralization
Neutralization occurs when an arrhenius acid reacts with an arrhenius base to form a salt and water.
Which pH value indicates the most acidic solution?
a) 2 b) 5
c) 7 d) 10
a) 2
Below 7 is an acidic solution. The farther away below 7, the pH is, the stronger the acid.
STATE the color of bromothymol blue indicator in a sample of vinegar that has a pH of 2.4.
Yellow
According to Table M, bromothymol blue turns yellow in a solution with a pH of 6 and below.
Which laboratory process is used to determine the concentration of one solution by using a volume of another solution of known concentration?
a) crystallization b) distillation
c) filtration d) titration
d) titration
This is the definition of a titration process.
Which statement describes an electrolyte?
a) An electrolyte conducts an electric current as a solid and dissolves in water.
b) An electrolyte conducts an electric current as a solid and does not dissolve in water.
c) When an electrolyte dissolves in water, the resulting solution does not conduct an electric current
d) When an electrolyte dissolves in water, the resulting solution conducts and electric current
d) When an electrolyte dissolves in water, the resulting solution conducts and electric current
Acids, Bases and Salts are all electrolytes because they produce ions in solution, which allow them to conduct electricity.
The concentration of which ion is increased when LiOH is dissolved in water?
a) hydroxide ion b) hydrogen ion
c) hydronium ion d) halide ion
a) hydroxide ion
LiOH is a base, which will produce OH- ions when dissolved in water:
LiOH (aq) → Li+ (aq) + OH- (aq)
Which word equation represents a neutralization reaction?
a) base + acid→ salt + water
b) base + salt→ water + acid
c) salt + acid→ base + water
d) salt + water→ acid + base
a) base + acid→ salt + water
Neutralization occurs when an arrhenius acid reacts with an arrhenius base to form a salt and water.
What would be the pH value for distilled water?
7
Distilled water is neutral and should have a pH of 7.
A solution with a pH of 11 is first tested with phenolphthalein and then with litmus. What is the color of each indicator in this solution?
a) phenolphthalein is colorless and litmus is blue
b) phenolphthalein is colorless and litmus is red
c) phenolphthalein is pink and litmus is blue
d) phenolphthalein is pink and litmus is red
c) phenolphthalein is pink and litmus is blue
A pH of 11 is a basic solution. According to Table M, phenolphthalein turns pink and litmus turns blue.
WRITE out the TITRATION formula.
MaVa = MbVb
Ma - Molarity (concentration) of acid
Va- Volume of acid
Mb - Molarity (concentration) of base
Vb- Volume of base
Which of these substances could be considered an electrolyte?
a) CCl4 b) H2SO4
c) SiO2 d) C6H12O6
b) H2SO4
Acids, Bases and Salts are all electrolytes because they produce ions in solution, which allow them to conduct electricity. H2SO4 is an acid.
Which pair of compounds represents one Arrhenius acid and one Arrhenius base?
a) CH3OH and NaOH b) HNO3 and NaOH
c) CH3OH and HCl d) HNO3 and HCl
b) HNO3 and NaOH
Arrhenius acids produce H+ ions in water and Arrhenius bases produce OH- ions in water:
HNO3 (aq)→ H+ (aq) + NO3-(aq)
NaOH (aq) → Na + (aq) + OH- (aq)
Which of the equations below represents a neutralization reaction?
a) 6 Li (s) + N2 (g) → 2 Li3N (s)
b) 2 Mg (s) + O2 (g) → 2 MgO (s)
c) 2 KOH (aq) + H2SO4 (aq) → K2SO4 (aq) + 2 H2O (l)
d) Pb(NO3)2 (aq) + K2CrO4 (aq) → 2KNO3 (aq) + PbCrO4 (s)
c) 2 KOH (aq) + H2SO4 (aq) → K2SO4 (aq) + 2 H2O (l)
Neutralization occurs when an arrhenius acid reacts with an arrhenius base to form a salt and water. KOH (aq) is a base and H2SO4(aq) is an acid.
Compared to a 1.0 liter aqueous solution with a pH of 7.0, a 1.0 -liter aqueous solution with a pH of 5.0 contains
a) 10 times more hydronium ions
b) 100 times more hydronium ions
c) 10 times more hydroxide ions
d) 100 times more hydroxide ions
b) 100 times more hydronium ions
The pH scale goes by tenfold per unit. Since 5 is two units away from 7, it is 102 times more acidic. Acids can produce either hydrogen (H+) or hydronium (H3O+).
Which pH indicator below is blue in a solution that has a pH of 5.6?
a) bromocresol green
b) bromothymol blue
c) methyl orange
d) thymol blue
a) bromocresol green
Bromocresol green will turn blue in a solution with a pH of 5.4 and above according to Table M.
Which of the pH indicators on Table M of the Chemistry Reference Table is usually used in a titration experiment to indicate that the reaction has been fully neutralized.
phenolphthalein
Phenolphthalein will turn a light pink color in a neutral solution, which has a pH of around 7.
Salt (NaCl) can be considered to be an electrolyte.
TRUE OR FALSE ???
TRUE
Acids, Bases and Salts are all electrolytes because they produce ions in solution, which allow them to conduct electricity.
NaCl (s) → Na+ (aq) + Cl-(aq)
The compound NaOH (s) dissolves in water to yield
(a) hydronium ions as the only negative ions
(b) hydronium ions as the only positive ions
(c) hydroxide ions as the only negative ions
(d) hydroxide ions as the only positive ions
(c) hydroxide ions as the only negative ions
Arrhenius bases produce OH- ions in water, which is a negative ion.
NaOH → Na+ (aq) + OH- (aq)
Which solution will react with LiOH (aq) to produce a salt and water?
a) KCl (aq) b) CaO (aq)
c) NaOH (aq) d) H2SO4 (aq)
d) H2SO4 (aq)
LiOH, is a base which needs to react with an acid to be able to form a salt and water. H2SO4 (aq) is sulfuric acid. *TABLE K AND L*
The pH of an aqueous solution changes from 4 to 3 when the hydrogen concentration in the solution is
(a) decreases by a factors of 10
(b) increases by a factor of 10
(c) decreases by a factor 100
(d) increases by a factor of 100
b) increases by a factor of 10
As you go down the pH, the solution gets more acidic so it increases in hydrogen concentration.
The pH scale goes by tenfold per unit. So the space between a pH of 4 and 3 is 10.
Which statement correctly describes a solution with a pH of 4?
(a) It has a higher concentration of H3O+ than OH- and causes litmus to turn blue.
(b) It has a lower concentration of H3O+ than OH- and causes litmus to turn blue.
(c) It has a higher concentration of H3O+ than OH- and causes litmus to turn red.
(d) It has a lower concentration of H3O+ than OH- and causes litmus to turn red.
(c) It has a higher concentration of H3O+ than OH- and causes litmus to turn red.
A pH of 4 means the solution is acidic, which has a higher concentration of H3O+ ions and will turn litmus paper red.
In a titration, 5.0 mL of a 2.0 M NaOH (aq) solution exactly neutralizes 10.0 mL of an HCl (aq) solution. What is the concentration of the HCl (aq) solution?
a) 1.0 M b) 2.0 M
c) 10.0 M d) 20.0 M
a) 1.0 M
MaVa = MbVb
Ma(10) = (2.0)(5.0)
Ma(10) = 10
Ma = 1.0 M
Which solution below would probably be the best conductor of an electric current?
a) 0.001 mole of NaCl dissolved in 1000. mL of water
b) 0.005 mole of NaCl dissolved in 1000. mL of water
c) 0.1 mole of NaCl dissolved in 1000. mL of water
d) 0.05 mole of NaCl dissolved in 1000. mL of water
c) 0.1 mole of NaCl dissolved in 1000. mL of water
The greater the concentration of solute, the more ions will be produced and the better the conductivity of electricity there will be.
What is ANOTHER chemical formula that can be used to express the hydrogen ion (H+) ions released by acids when they react with water?
Hydronium (H3O+) ion
When an acid reacts with water, hydronium ions are produced.
HCl (aq) + H2O (l) → H3O+ (aq) Cl- (aq)
WRITE the chemical formula of the missing product that would form in the following neutralization equation below:
2 NaOH (aq) + H2SO4 (aq) → 2 H2O (l) + ____________ (aq)
Na2SO4
Products of a neutralization reaction are always a salt (ionic compound) and water. Since the water is alread present, the salt left is Na2SO4. There are 2 Na and 1 SO4 in the reactant so the correct formula of the salt would be Na2SO4.
STATE the pH value of a sample that has ten times fewer hydronium ions than an equal volume of a vinegar sample with a pH value of 2.4.
3.4
Two samples of the same rainwater are tested using two pH indicators at an environmental lab. The first pH indicator, Methyl Orange, reveals a distinct yellow color when added to the sample. The second pH indicator, Litmus, turns red when placed in contact with the water sample.
IDENTIFY a possible pH value for the rainwater.
Either 4.4 or 4.5
Methyl Orange after a pH of 4.4 is yellow. Litmus is red below a pH of 4.5.
In a titration, 20.0 milliliters of 0.15 M HCl(aq) is exactly neutralized by 18.0 milliliters of KOH(aq). Determine the concentration of the KOH(aq).
0.166 M or 0.17 M
MaVa = MbVb
(0.15)(20.0)= Mb(18.0)
3=Mb(18)
3/18 = 0.1666 = Mb
EXPLAIN in terms of particles, why HC2H3O2 (aq), also known as acetic acid-vinegar, can conduct an electric current.
HC2H3O2 (aq) is acetic acid also known as vinegar. Acids are electrolytes and can conduct an electric current because they produce hydrogen ions when dissolved in water than can conduct electricity.