Vet Labs Sat 2 Rev Flashcards

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1
Q

Differentiate between precision and accuracy

A

Accuracy refers to how close a measurement is to the true or accepted value. Precision refers to how close measurements of the same item are to each other

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2
Q

Comprehend the significance of significant figures in reporting measurement results.

A

By using significant figures, we can show how precise a number is.

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3
Q

Determine the number of significant figures in a measurement.

A
  1. 0.00721800
  2. 1690020.00
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4
Q

Provide an example of how to improve the repeatability of a measurement.

A
  1. Properly Label Everything.
  2. Avoid Expired Reagents or Perform
    Quality Control Tests.
  3. Design Your Experimental Protocols
    in Detail.
  4. Include Appropriate Controls and
    Practices.
  5. Assign Work Appropriately.
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5
Q

Understand the concept of measurement error.

A

refers to the difference between the observed value (the result of measurement) and the actual value of what we are measuring.

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6
Q

List and know the seven base units of the International System of Units (SI).

A
  • Length - meter (m)
  • Time - second (s)
  • Amount of substance - mole (mole)
  • Electric current - ampere (A)
  • Temperature - kelvin (K)
  • Luminous intensity - candela (cd)
  • Mass - kilogram (kg)
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7
Q

Convert measurements between different units (e.g., kilometers to meters, milliliters to liters).

A

0.078km –> m

78000m –> km

782ml –> L

120L –> ml

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8
Q

Know the primary purpose of titration.

A

to determine the concentration of a substance by reacting that substance with another substance of known concentration in a reaction.

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9
Q

The process of performing titration

A
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10
Q

Endpoint

A

The point during a titration when an indicator shows that the amount of reactant necessary for a complete reaction has been added to a solution.

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11
Q

Importance of Endpoint

A

Allows researchers to obtain the precise measurement of the analyte concentrations in solution

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12
Q

Define repeatability in the context of laboratory measurements.

A

A measure of the ability of the method to generate similar results for multiple preparations of the same sample.

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13
Q

Describe the purpose of performing tests in a laboratory setting.

A

The purpose of performing tests in a laboratory setting is to ensure the results are accurate, there is no contamination between chemicals and all possible risks are minimised (PPE)

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14
Q

How does titration help in determining the concentration of an unknown solution?

A

Titration helps in determining the concentration of an unknown solution by adding the titrant (known solution) placed in the buret to a known quantity of the analyte (the unknown solution) until the reaction is complete. Knowing the volume of titrant added allows the determination of the concentration of the unknown.

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15
Q

Explain the role of an indicator in a titration process.

A

To identify the equivalence or the end point of a reaction where pH change occurs.

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16
Q

Describe a scenario where titration is used in your job role.

A

Product development and quality control - In food processing, acid or base titration determines the acidity of fruit juice.

17
Q

Describe a pre-use safety check you would perform on laboratory equipment. (e.g pick a piece of equipment and describe the checks you would use)

A

possible general pre-use safety checklist for lab equip

  • check for remaining solids (e.g residue on glass)
  • check for glass chippings
  • check for cracks
  • check for general damage
  • check for possible missing parts
  • check for accuracy (volumetric flask) idk
17
Q

How can improper equipment checks affect test results?

A
  • Provides false readings
  • inaccurate measurements
  • spill/chemical contamination
18
Q

How can you minimise the uncertainty in a measurement?

A

Calibrate your instruments and take multiple measurements to average out. Reduce random errors by keeping conditions stable and repeating tests to spot and remove odd results.

19
Q

What role does calibration play in controlling measurement uncertainty?

A

Ensures that the instruments produce results that reflect reality as closely as possible

20
Q

Explain the concept of traceability in the context of laboratory work.

A

Traceability is how we know that a measurement is accurate.
- involves linking the value that we say we have achieved, to an international measure.
- involves comparisons in measurements and considers how many steps are involved.

21
Q

Why is legal traceability important in laboratory testing?

A

Credibility of results can have far-reaching consequences in terms of public health, safety and in legal judgments based on laboratory reports

22
Q

How do you ensure traceability of a sample from collection to reporting?

A

Implement a Secure Database or Electronic System

23
Q

What constitutes an unexpected or unusual result in a laboratory test?

A

Results that lie outside the laboratory reference ranges

24
Q

What procedures should you follow if you encounter an unusual result?

A
  • check your data and methodology for errors
  • Fix errors
  • rinse and repeat the experiment
25
Q

What are the procedures for coding and entering data in a laboratory setting?

A
  • Record in log book
  • electronically
  • record straight away
  • store in multiple locations
26
Q

How do you maintain and file records securely?

A

Have a secure off-site storage location, which may include cloud storage.

27
Q

What steps should you take to rectify mistakes in data entry?

A
  • Identify the source and scope of the error.
  • Choose the best method to correct the error.
  • Test and verify the correction.
  • Document and report the correction.
  • Monitor and evaluate the correction.
28
Q

What is the difference between quantitative data and qualitative data in the context of laboratory measurements?

A

Quantitative data is data involving numbers, usually involves calculating mass, volume, area etc

Qualitative data is data involving words and it is used to describe things, usually involves colours, smell, texture etc

29
Q

Example of a laboratory test that yields quantitative data and another that yields qualitative data.

A

Yields quantitative data: blood glucose levels

Yields qualitative data: colour of different metals burning in fire

30
Q

Define random error and provide an example of how it might occur in a laboratory setting.

A

Definition: An error in measurement caused by factors which vary from one measurement to another.

Example: measuring in a beaker then transferring the liquid to a measuring cylinder - idk

31
Q

How can operator error and equipment error impact the reliability of test results? Provide an example for each.

A

Both operator error and equipment error can impact the reliability of test results by providing false information about the test, an example is a balance that is faulty therefore providing false weigh of ingredients.