Question 1

Match the term with the appropriate definition.
-specific gravity

Accepted Answer

A)  the amount of matter per unit volume of a substance
B)  relates the weight of 1 mL of a solution and the weight of 1 mL of pure water at 4°C (1 g)  B

Question 2

A significant figure should contain only the digits in a number needed to express the precision of the measurement.

Accepted Answer

A) True 
 B)False  True

Question 3

The more digits that are used in laboratory assay results,the more precise the answer is.

Accepted Answer

A) True 
 B)False  False

Question 4

Laboratory results should only contain the digits necessary for the precision of the determination.

Accepted Answer

A) True 
 B)False

Question 5

In rounding off numbers:

Accepted Answer

A)   when the digit next to the last one to be retained is less than 5, the last digit should be left unchanged.
B)   when the digit next to the last one to be retained is greater than 5, the last digit is increased by 1.
C)   if the additional digit is 5, the last digit reported is changed to the nearest even number.
D)   follow all of the above.

Question 6

Match the following terms with an appropriate definition.
-working standard solution

Accepted Answer

A)  a solution prepared from a stock solution and usually stored in the refrigerator
B)  one that contains a known, exact amount of the substance being measured
C)  one that contains reagents used in the procedure but not the substance to be measured

Question 7

Report a laboratory result with the most number of significant figures as the accuracy of the final result.

Accepted Answer

A) True 
 B)False

Question 8

Match the term with the appropriate definition.
-density

Accepted Answer

A)  the amount of matter per unit volume of a substance
B)  relates the weight of 1 mL of a solution and the weight of 1 mL of pure water at 4°C (1 g)

Question 9

If a serum specimen is diluted 1:2 with buffer beginning in tube 2 and serially rediluted 1:2 in each of five subsequent test tubes,what is the concentration of serum in tube 5?

Accepted Answer

A)   0.5
B)   0.25
C)   0.125
D)   0.06

Question 10

Match the following terms with an appropriate definition.
-standard solution

Accepted Answer

A)  a solution prepared from a stock solution and usually stored in the refrigerator
B)  one that contains a known, exact amount of the substance being measured
C)  one that contains reagents used in the procedure but not the substance to be measured

Question 11

What is the molarity of a solution containing 50 g of NaCl per liter?

Accepted Answer

A)   0.2M
B)   0.5M
C)   0.9M
D)   1.5M

Question 12

Match the following terms with an appropriate definition.
-blank solution

Accepted Answer

A)  a solution prepared from a stock solution and usually stored in the refrigerator
B)  one that contains a known, exact amount of the substance being measured
C)  one that contains reagents used in the procedure but not the substance to be measured

Question 13

Calculate the concentration expressed in percent,if 10 g of NaOH is diluted to 500 mL with water.

Accepted Answer

A)   1%
B)   2%
C)   5%
D)   10%

Question 14

The term dilution refers to:

Accepted Answer

A)   the volume or number of parts of the substance to be diluted in the total volume.
B)   the volume or number of parts of the substance to be diluted in the parts of the final solution.
C)   an expression of concentration that indicates the relative amount of substance in solution.
D)   all of the above.

Exam 7: Laboratory Mathematics and Solution Preparation

Match the term with the appropriate definition. -specific gravity

A significant figure should contain only the digits in a number needed to express the precision of the measurement.

The more digits that are used in laboratory assay results,the more precise the answer is.

Laboratory results should only contain the digits necessary for the precision of the determination.

In rounding off numbers:

Match the following terms with an appropriate definition. -working standard solution

Report a laboratory result with the most number of significant figures as the accuracy of the final result.

Match the term with the appropriate definition. -density

If a serum specimen is diluted 1:2 with buffer beginning in tube 2 and serially rediluted 1:2 in each of five subsequent test tubes,what is the concentration of serum in tube 5?

Match the following terms with an appropriate definition. -standard solution

What is the molarity of a solution containing 50 g of NaCl per liter?

Match the following terms with an appropriate definition. -blank solution

Calculate the concentration expressed in percent,if 10 g of NaOH is diluted to 500 mL with water.

The term dilution refers to: