7 LABORATORY MATHEMATICS AND SOLUTION PREPARATION Flashcards
How would 6.32 be rounded off to one less decimal place?
a. 6.32
b. 6.4
c. 7.0
d. 6.3
d. 6.3
How would 15.57 be rounded off to one less decimal place?
a. 15.6
b. 15.5
c. 16.0
d. 15.0
a. 15.6
How would 25.96 be rounded off to one less decimal place?
a. 26.0
b. 25.9
c. 25.6
d. 26.96
a. 26.0
The exponent 10^−2 represents:
a. 100
b. 1000
c. 0.1
d. 0.01
d. 0.01
A unique characteristic of specific gravity versus density is that specific gravity is:
a. The amount of matter per unit volume of a substance
b. That all substances have this property
c. That it represents size of substance
d. That it is applicable only to solutions
d. That it is applicable only to solutions
Molarity is:
a. The amount of one substance relative to the amounts
of other substances in the solution
b. Relative concentrations of the components of a mixture
c. The gram-molecular mass (or weight) of a compound per liter of solution
d. Expression of one amount relative to another amount
c. The gram-molecular mass (or weight) of a compound per liter of solution
Dilution is:
a. The amount of one substance relative to the amounts of other substances in the solution
b. Relative concentrations of the components of a mixture
c. The gram-molecular mass (or weight) of a compound per liter of solution
d. Expression of one amount relative to another amount
b. Relative concentrations of the components of a mixture
Three grams (3 g) of solute in 100mL of solvent equals _____% (w/v).
a. 0.3
b. 3
c. 30
d. 300
b. 3
Twenty grams (20 g) of solute dissolved in 1L of solvent equals _____% (w/v).
a. 0.2
b. 2
c. 20
d. 200
b. 2
If 6mL of liquid is placed in a volumetric flask and the volume is brought to 100mL total, the solution is what percent of liquid?
a. 0.6%
b. 6%
c. 60%
d. None of the above
b. 6%
How many grams of NaCl would be used to prepare 1000mL of a 5% (w/v) solution of NaCl?
a. 0.5 g
b. 5 g
c. 50 g
d. 500 g
c. 50 g
If there is 25 g of NaCl per liter of solution, what is the molarity?
a. 025M
b. 0.43M
c. 0.5M
d. 1.0M
b. 0.43M
How many grams of NaCl are needed to prepare 1000mL of a 0.5M solution of NaCl?
a. 5 g
b. 15 g
c. 29 g
d. 58.4 g
c. 29 g
How much calcium chloride (CaCl2) is needed to prepare 500mL of a 0.5M solution of CaCl2?
a. 27.7 g
b. 40.0 g
c. 57.8 g
d. 115.6 g
a. 27.7 g
What is the correct formula for calculating a percent (w/v) solution?
a. Grams of solute/Volume of solution×100
b. Grams of solute×Volume of solvent×100
c. Volume of solvent/Grams of solute×100
d. Grams of solute×Volume of solvent/100
a. Grams of solute/Volume of solution×100
If a solution contains 20 g of solute dissolved in 0.5L of water, what is the percentage of this solution?
a. 2%
b. 4%
c. 6%
d. 8%
b. 4%
How is a 25% w/w solution prepared?
a. 0.25 g solute and 75 g solvent
b. 2.5 g solute and 97.5 g solvent
c. 25 g solute and 75 g solvent
d. 75 g solute and 25 g solvent
c. 25 g solute and 75 g solvent
How many milliliters (mL) of bleach in an original bottle are needed to prepare a 10% solution?
a. 0.1mL bleach and 100mL water
b. 1.0mL bleach and 90mL water
c. 10mL bleach and 90mL water
d. Bleach is already a 10% solution in the original bottle
c. 10mL bleach and 90mL water
What is the dilution factor if 0.5mL of serum is added to 2mL of diluent?
a. 0.5
b. 1.5
c. 2.5
d. 5
d. 5
What volume of 25% alcohol is needed to prepare 500mL of 15% alcohol?
a. 30mL
b. 300mL
c. 350mL
d. 375mL
b. 300mL
A ratio is:
a. The amount of one substance relative to the amounts of other substances in the solution
b. Relative concentrations of the components of a mixture
c. The gram-molecular mass (or weight) of a compound per liter of solution
d. Expression of one amount relative to another amount
d. Expression of one amount relative to another amount
If only 25mL of a 9% saline solution is available in the laboratory, how many mL of 5% saline solution can be prepared using all available saline solution?
a. 4.5mL
b. 25.0mL
c. 45.0mL
d. 100mL
c. 45.0mL
Concentration is:
a. The amount of one substance relative to the amounts of other substances in the solution
b. Relative concentrations of the components of a mixture
c. The gram-molecular mass (or weight) of a compound per liter of solution
d. Expression of one amount relative to another amount
a. The amount of one substance relative to the amounts of other substances in the solution
To dilute a serum specimen 1:10, _____ parts of serum would be added to _____ parts distilled water.
a. 1, 10
b. 1, 9
c. 0.5, 4.5
d. Both b and c
b. 1, 9
If 0.1mL of serum, 5mL of reagent, and 4.9mL of distilled water are mixed together, what is the dilution of the serum in the final solution?
a. 1:5
b. 1:10
c. 1:50
d. 1:100
d. 1:100
If a glucose standard solution contains 10mg/dL of glucose, a 1:10 dilution of this standard contains how much glucose?
a. 0.01mg/dL
b. 0.1mg/dL
c. 1mg/dL
d. None of the above
c. 1mg/dL
What is the dilution factor if 4mL of serum is added to 12mL of diluent?
a. 3
b. 4
c. 12
d. 15
b. 4
Serum is diluted with an equal amount of diluent (such as tube #1, 1:2 and tube #2, 1:2). What is the concentration in tube #2 if the original concentration was 100mg/dL?
a. 12.5mg/dL
b. 25.0mg/dL
c. 50.0mg/dL
d. 75.0mg/dL
b. 25.0mg/dL
If a total of 125mL of a 10% solution is diluted to 500mL in a 500-mL volumetric flask, what is the concentration of the resulting new solution?
a. 0.25%
b. 2.5%
c. 25%
d. None of the above
b. 2.5%
You are asked to make a 1:2 dilution using 1.5mL of serum. How much diluent do you need to use?
a. 1.5mL
b. 3.0mL
c. 15mL
d. 30mL
a. 1.5mL
Which of the following “recipes” gives you a 1:5 dilution?
a. 0.25mL serum+4.75mL of diluent
b. 2mL of serum+18mL of diluent
c. 0.25mL serum+1mL of diluent
d. 1.5mL serum+13.5mL of diluent
c. 0.25mL serum+1mL of diluent
The dilution created by 1.5 mL serum + 13.5 mL of diluent is:
a. 1:20
b. 1:10
c. 1:100
d. 1:1000
b. 1:10
If you make a five-tube twofold dilution using 2mL of serum, what is the concentration of serum in tube #4?
a. 0.125mL
b. 0.25mL
c. 1mL
d. 2mL
a. 0.125mL
