Exam 1 TopHat Questions

Question 1

A sample with a different chemical composition from place to place is a ________ sample?

Answer 1

heterogeneous

Question 2

True or False: It is essential to obtain a representative sample to analyze

Answer 2

true

Question 3

After a liquid is used to extract an analyte from a solid sample, the liquid is _____ from the sample.

Answer 3

decanted

Question 4

Why is a calibration curve, or a standard curve, necessary in chemical analysis?

Answer 4

to measure the detector response for different analyte concentrations

Question 5

True or False: Random errors can be eliminated and reduced by better techniques

Answer 5

false

Question 6

Which of the following is NOT a characteristic of random (or indeterminate) error?

Answer 6

it arises from a flaw in equipment or the design of an experiment

Question 7

The uncertainty of a buret is +- 0.05 mL. The true value of a reading of 17.23 mL is in the range _____?

Answer 7

17.18 to 17.28 mL

Question 8

True or False: A standard deviation close to zero means that the data points are close to the mean of the set

Answer 8

true

Question 9

True or False: A standard deviation close to zero means that the points in a data set are close to the “true” value

Answer 9

false

Question 10

You can decrease the uncertainty by a factor of 4 by increasing the number of measurements by a factor of ______

Answer 10

16

Question 11

True or False: When Fcalculated is greater than Ftable at the 95% confidence level, there is a less than 5% chance that the two data sets come from the same populations with the same population standard deviation.

Answer 11

true

Question 12

Which statement is NOT true for the method of least squares?

Answer 12

the equation for a straight line is y = bx +m, where m is the slope and b is the y-intercept

Question 13

The linear range is _____

Answer 13

the concentration range over which the instrumental response is a linear function of the analyte concentration

Question 14

A result that says a concentration is below a certain limit but it is actually above a the limit is a ______

Answer 14

false negative

Question 15

When a reaction is reversed, how is the equilibrium constant of the reversed reaction (K’) related to the equilibrium constant (K) of the original reaction?

Answer 15

K’ = 1/K

Question 16

True or False: A reaction is favored if delta G is positive

Answer 16

false