Laboratory Techniques: Safety, Glassware, Measurement, Data Analysis

Question 1

To correctly use a graduated cylinder, which technique should you follow?

Accepted Answer

Hold the cylinder vertically and carefully fill it to the desired volume.

Answer

Tilt the cylinder slightly and fill it slightly above the desired volume.

Answer

Hold the cylinder horizontally and fill it completely.

Question 2

What is the primary purpose of a calibration curve?

Accepted Answer

To establish the correlation between the concentration of a sample and its absorbance.

Answer

To determine the molar mass of a substance.

Answer

To identify the presence of a specific compound.

Question 3

What does the standard deviation primarily indicate?

Accepted Answer

The precision of a measurement

Answer

The accuracy of a measurement

Answer

The range of possible values

Question 4

What is the primary function of a buffer solution?

Accepted Answer

To maintain a stable pH

Answer

To precipitate ions in solution

Answer

To oxidize or reduce analytes

Question 5

Why are buffer solutions crucial for maintaining pH stability in biological systems?

Accepted Answer

They neutralize added acids or bases, minimizing pH changes.

Answer

They increase the pH of acidic solutions.

Answer

They decrease the pH of basic solutions.

Answer

They prevent the formation of precipitates.

Question 6

Which of the following methods is commonly employed for separating a solid from a liquid mixture?

Accepted Answer

Filtration

Answer

Distillation

Answer

Chromatography

Answer

Centrifugation

Question 7

When plotting a graph of experimental data, the variable that is manipulated or controlled is typically represented on the:

Accepted Answer

x-axis

Answer

y-axis

Answer

Both axes

Answer

Neither axis

Question 8

Which of the following laboratory techniques requires the use of a burette?

Accepted Answer

Titration

Answer

Filtration

Answer

Distillation

Answer

Chromatography

Question 9

Which of the following laboratory techniques is **NOT** directly addressed in this unit?

Accepted Answer

Cell culture techniques

Answer

Safety procedures

Answer

Glassware handling

Answer

Accurate measurement techniques

Question 10

When preparing a solution, which of the following actions **lowers** the risk of splattering?

Accepted Answer

Adding the liquid solvent to the solid solute

Answer

Adding the solid solute to the liquid solvent

Answer

Adding both the solute and solvent simultaneously

Answer

The order of addition does not matter

Question 11

To accurately determine the concentration of an unknown solution, the most appropriate analytical technique is:

Accepted Answer

Titration

Answer

Spectrophotometry

Answer

Gas chromatography

Answer

Nuclear magnetic resonance spectroscopy

Question 12

When working with hazardous chemicals, **all** of the following precautions **must** be taken **EXCEPT**:

Accepted Answer

Eating or drinking in the laboratory

Answer

Wearing appropriate personal protective equipment

Answer

Following the manufacturer's safety instructions

Answer

Disposing of waste properly

Question 13

When handling flammable liquids, **all** of the following precautions **must** be observed **EXCEPT**:

Accepted Answer

Transferring them between containers using a glass pipette

Answer

Keeping them away from open flames

Answer

Storing them in a cool, well-ventilated area

Answer

Using a fume hood when working with them

Question 14

Which glassware is **primarily used** for heating liquids over a Bunsen burner?

Accepted Answer

Conical flask

Answer

Beaker

Answer

Test tube

Answer

Volumetric flask

Question 15

When measuring the pH of a solution using a pH meter, **all** of the following steps **must** be followed **EXCEPT**:

Accepted Answer

Touching the electrode with your fingers

Answer

Calibrating the meter before use

Answer

Rinsing the electrode with distilled water between measurements

Answer

Reading the display carefully and recording the value accurately

Question 16

The primary purpose of a volumetric flask is to:

Accepted Answer

Prepare solutions of precise volume

Answer

Store chemicals

Answer

Measure small volumes of liquid

Answer

Mix different liquids

Question 17

When using a burette, the liquid level should be read at the:

Accepted Answer

Top of the meniscus

Answer

Bottom of the meniscus

Answer

Middle of the meniscus

Answer

Highest point of the liquid

Question 18

To measure very small volumes of liquid (less than 1 mL), the appropriate type of pipette is a:

Accepted Answer

Micropipette

Answer

Graduated pipette

Answer

Volumetric pipette

Answer

Dropper pipette

Question 19

In a titration, the endpoint is reached when:

Accepted Answer

The indicator changes colour

Answer

The solution turns a specific colour

Answer

The burette reading matches the initial volume

Answer

The solution stops bubbling

Question 20

What is the primary purpose of a calibration curve?

Accepted Answer

To determine the relationship between absorbance and concentration

Answer

To calculate the unknown concentration of a sample

Answer

To verify the accuracy of a spectrophotometer

Answer

To adjust for background noise

Question 21

Which of the following is a crucial safety precaution to adhere to in a chemistry laboratory?

Accepted Answer

Wearing appropriate personal protective equipment

Answer

Eating snacks or drinking beverages in the laboratory

Answer

Conducting experiments without supervision

Answer

Leaving hazardous materials unattended

Question 22

Which type of glassware is specifically designed for measuring precise volumes of liquids?

Accepted Answer

Volumetric pipette

Answer

Graduated cylinder

Answer

Beaker

Answer

Flask

Question 23

Which method is commonly used to separate a mixture of two immiscible liquids?

Accepted Answer

Separating funnel

Answer

Filtration

Answer

Distillation

Answer

Chromatography

Question 24

To determine the concentration of a solution, the following formula is employed:

Accepted Answer

Concentration = Mass of solute / Volume of solution

Answer

Concentration = Volume of solution / Mass of solute

Answer

Concentration = Mass of solute / Mass of solution

Answer

Concentration = Volume of solution / Volume of solute

Question 25

Which of the following is not classified as a type of chromatography?

Accepted Answer

Titration

Answer

Paper chromatography

Answer

Thin-layer chromatography

Answer

Gel electrophoresis

Question 26

In a laboratory setting, what is the main reason for wearing a lab coat?

Accepted Answer

To prevent contamination between chemicals and the wearer's skin and clothing

Answer

To protect clothing from stains

Answer

To maintain a professional appearance

Answer

To minimize the risk of fire

Question 27

In the United Kingdom, the standard unit for measuring temperature is:

Accepted Answer

Celsius

Answer

Fahrenheit

Answer

Kelvin

Answer

Rankine

Question 28

When preparing a solution, the solute should be added to the:

Accepted Answer

Solvent

Answer

Diluent

Answer

Excipient

Answer

Buffer

Question 29

In a titration, the primary purpose of a burette is to:

Accepted Answer

Deliver a precise volume of solution

Answer

Measure the remaining volume of solution after titration

Answer

Mix the solution

Answer

Heat the solution

Question 30

Molarity of a solution is defined as the number of:

Accepted Answer

Moles of solute per litre of solution

Answer

Moles of solute per kilogram of solvent

Answer

Moles of solvent per litre of solution

Answer

Grams of solute per litre of solution

Question 31

The primary role of a catalyst in a chemical reaction is to:

Accepted Answer

Decrease the activation energy of the reaction

Answer

Increase the activation energy of the reaction

Answer

Alter the products of the reaction

Answer

Slow down the reaction rate

Question 32

Identify a potential source of error in laboratory experiments:

Accepted Answer

Incorrectly calibrated equipment

Accepted Answer

Unstable environmental conditions

Accepted Answer

Errors in data recording and analysis

Answer

Employing high-quality reagents and materials

Question 33

In a laboratory, which action is discouraged?

Accepted Answer

Eating or drinking

Answer

Wearing safety gear

Answer

Following experiment instructions

Answer

Disposing of chemicals responsibly

Question 34

Which of the following is not a type of burette?

Accepted Answer

Volumetric flask

Answer

Graduated burette

Answer

Automatic burette

Answer

Gas burette

Question 35

When working with concentrated acids, which safety precaution is essential?

Accepted Answer

Wear appropriate personal protective equipment (PPE) such as gloves, eye protection, and a lab coat.

Answer

Keep the work area well-ventilated.

Answer

Dispose of chemicals properly.

Question 36

Which type of glassware is specifically designed to contain and heat liquids?

Accepted Answer

Beaker

Answer

Test tube

Answer

Pipette

Answer

Conical flask

Question 37

In a titration experiment, what is the primary purpose of using a burette?

Accepted Answer

To deliver precise volumes of solution accurately.

Answer

To mix chemical solutions.

Answer

To measure the volume of liquids.

Answer

To store and dispense large volumes of chemicals.

Question 38

Which of the following is a recognized method of data analysis in laboratory experiments?

Accepted Answer

Calculating the mean or average of multiple measurements.

Answer

Wearing appropriate safety gear.

Answer

Reading the volume from a volumetric flask.

Answer

Using a pipette to transfer liquids.

Question 39

In the context of laboratory measurements, what is the distinction between precision and accuracy?

Accepted Answer

Precision refers to the consistency of repeated measurements, while accuracy indicates their closeness to the true or accepted value.

Answer

Precision and accuracy are synonymous terms with no distinction.

Question 40

What is the main purpose of constructing a calibration curve in analytical chemistry?

Accepted Answer

To establish the relationship between the concentration of an analyte and its measurable property, allowing for accurate quantification.

Answer

To determine the accuracy of a measuring instrument.

Answer

To identify unknown substances based on their spectral properties.

Question 41

Which of the following glassware is not classified as volumetric glassware?

Accepted Answer

Beaker

Answer

Graduated cylinder

Answer

Pipette

Answer

Burette

Question 42

When disposing of broken glassware in a laboratory setting, which method is considered the safest and most appropriate?

Accepted Answer

Carefully place the broken pieces in a designated sharps container.

Answer

Leave the broken pieces on the bench for the cleaner to handle.

Answer

Rinse the broken pieces with water and discard them in the regular trash.