Everything
What is the name of the theory that defines acids as proton donors and bases as proton acceptors?
Bronsted-Lowry theory
What is the pOH of a solution with a pH of 4?
A - 5
B - 10^-10
C - 10
D - 10^-4
A - 5 (14-4 does not equal 5)
B - 10^-10 (Not asking for concentration)
C - 10 (14-4 = 10)
D - 10^-4 (Not asking for concentration)
Acids typically taste bitter.
A - True
B - False
A - True
B - False (Acids taste sour)
The reaction that occurs when an acid reacts with a base is called _____
The reaction that occurs when an acid reacts with a base is called neutralization. (When an acid and a base react to form water and a salt)
Which of the following are purposes of a titration? (Choose all that apply)
A - To determine the concentration of an unknown solution
B - To identify the pKa of a weak acid
C - To measure the purity of a substance
D - To find the equivalence point
A - To determine the concentration of an unknown solution
B - To identify the pKa of a weak acid
C - To measure the purity of a substance
D - To find the equivalence point
A) Correct, one of the primary purposes of titration is to determine the concentration of an unknown solution)
B) Incorrect, determining the pKa of a weak acid involves pH measurements, not titration
C) Incorrect, directly measuring for purity is found by techniques like chromatography
D) Correct, the equivalence point is the point in a titration when enough titrant is added to completely neutralize it.
What is the purpose of titration?
To determine the concentration of an unknown solution.
If a solution has a pH of 7, what is its hydrogen ion concentration?
A - 7
B - 1x10^7
C - 1x10^-7
D - 1x10^-14
A - 7 (formula is 10^-pH)
B - 1x10^7 (No negative sign)
C - 1x10^-7 (10^-7 = 1x10^-7)
D - 1x10^-14 (formula is 10^-pH)
Common examples of bases are: Lemons, oranges, vinegar, urine, sulfuric acid, hydrochloric acid
A - True
B - False
A - True
B - False (These are common examples of acids, bases would be bleach, soap, toothpaste, etc)
The product of neutralization reaction, besides water, is called _____
The product of neutralization reaction, besides water, is called salt. (When neutralization occurs, the product is water and a salt)
What can be used to indicate the endpoint of a titration? (Choose all that apply)
A - Phenolphthalein
B - Litmus paper
C - pH meter
D - Conductivity meter
A - Phenolphthalein
B - Litmus paper
C - pH meter
D - Conductivity meter
All are correct because each indicator is used to detect when the solution is acidic or basic through color changes or other indications, which is enough to find the equivalence point.
What is used to detect the end point of a titration?
An indicator.
A solution at 26*C has a hydroxide ion concentration of 1x10^-3 M. What is its pH?
A - 11
B - 3
C - 10^-3
D - 10^-11
A - 11 (Convert to pOH using -log[OH], which is 3, then find the difference of that with 14, which is the pH, 11)
B - 3 (Using concentration of hydroxide, which is the pOH, question asks for pH)
C - 10^-3 (Not converted into pH)
D - 10^-7 (Not converted into pH)
A student places blue litmus paper inside of an unknown substance. The paper turns red, which indicates that the unknown substance is a base.
A - True
B - False
A - True
B - False (If the substance was a base, the blue litmus paper would remain blue. This indicates that it's an acid
In any neutralization reaction, the hydrogen ions from the acid combine with the hydroxide ions from the base to form ____.
Water (H2O)
What equipment is needed for a titration? (Choose all that apply)
A - Burette
B - Flask
C - Beaker
D - Graduated Cylinder
A - Burette
B - Flask
C - Beaker
D - Graduated Cylinder
A) Correct, a Burette is essential for calculating the precise volumes of the titrant
B) Correct, a flask is used to contain the solution being titrated
C) Incorrect, beakers aren't used because you can't see the color change clearly
D) Incorrect, graduated cylinders aren't precise enough
VolumexConcentration = Volume2 x Concentration2
(25 mL)(1 M) = (50mL)(X)
25=50x
25/50=x
x=.5
Which value is the weakest base?
A - 9 pH
B - 1 pOH
C - 6 pH
D - 6 pOH
A - 9 pH (D is the better option, but this is still considered a weak base)
B - 1 pOH (Considered a really strong base)
C - 6 pH (Considered an acid)
D - 6 pOH (A pOH of 6 is the closest to being neutral, but still considered a base)
Acids turn colorless when placed in phenolphthalein.
A - True
B - False
A - True (When placed in phenolphthalein, it appears colorless. Bases turn pink)
B - False
Neutralization reactions are a type of _____ reaction because they produce water.
Neutralization reactions are a type of exothermic reaction because they produce water.
(The reactions release heat because they form water)
Which statements are true about the endpoint of a titration? Choose all that apply.
A - It is where the titrant has completely neutralized.
B - It is indicated by a sharp pH change.
C - Always occurs at 7 pH.
A - It is where the titrant has completely neutralized.
B - It is indicated by a sharp pH change.
C - Always occurs at 7 pH.
A) Correct, the endpoint is reached when complete neutralization occurs, which is the purpose of titration
B) Correct, there is a sharp change in pH at the end and it's visible through indicators
C) Incorrect, the endpoint doesn't always occur at 7 pH because it depends on the acid.
What is the name of a substance that can be both an acid or base depending on the reaction?
An amphiprotic substance
The pH of gastric juice is approximately 1.4, what is the hydroxide ion concentration of gastric juice?
A - 1x10^-1.4 M
B - 1x10^-12.6 M
C - 12.6 M
D - 1.4 M
A - 1x10^-1.4 M (This is the hydrogen ion concentration, the question is asking for hydroxide ion concentration)
B - 1x10^-12.6 M (Convert the pH into pOH, which is 12.6, because it's asking for the hydroxide ion concentration. Then, use the formula 10^-pOH to find the concentration)
C - 12.6 M (This is pOH, asking for hydroxide ion concentration)
D - 1.4 M (This is pH, asking for hydroxide ion concentration)
Acids and bases both conduct electricity.
A - True
B - False
A - True (Both acids and bases conduct electricity because of the movement of the charged ions)
B - False
HNO3 + KOH → ___ + ____
HNO3 + KOH → H2O + KNO3
(neutralization occurs)
What properties could change during a titration? Choose all that apply.
A - pH
B - Color
C - Viscosity
D - Conductivity
A - pH
B - Color
C - Viscosity
D - Conductivity
A) Correct, pH changes during titration, visible with an indicator
B) Correct, color changes occur because of the indicator to detect neutralization
C) Incorrect, viscosity doesn't change
D) Correct, conductivity changes