Chapter 1: Experimental Chemistry

Question 1

What is the SI unit for time?

Answer 1

Second (s)

Question 2

What is the SI unit for temperature?

Answer 2

Kelvin (K)

Question 3

How is temperature in Kelvin calculated from degrees Celsius?

Answer 3

Temperature in K = Temperature in °C + 273

Question 4

What is the SI unit for mass?

Answer 4

Kilogram (kg)

Question 5

What is the SI unit for volume?

Answer 5

Cubic metre (m³)

Question 6

What are the two types of thermometers commonly used in laboratories?

Answer 6

Alcohol and mercury thermometers

Question 7

What is the advantage of digital thermometers?

Answer 7

They have a wider temperature range and can record data using data loggers

Question 8

What is the accuracy of a pipette?

Answer 8

Measures fixed volumes accurately, e.g., 10.0 cm³ or 25.0 cm³

Question 9

What is the accuracy of a volumetric flask?

Answer 9

Measures accurate fixed volumes that are larger, e.g., 100 cm³ or 250 cm³

Question 10

What is the accuracy of a measuring cylinder?

Answer 10

Measures a range of volumes to the nearest 0.5 cm³, e.g., 31.5 cm³ or 23.0 cm³

Question 11

What is the accuracy of a burette?

Answer 11

Measures a range of volumes to the nearest 0.05 cm³, e.g., 31.55 cm³ or 23.00 cm³

Question 12

Which method is used to collect gases insoluble in water?

Answer 12

Water displacement

Question 13

How are gases less dense than air collected?

Answer 13

Using upward delivery

Question 14

How are gases denser than air collected?

Answer 14

Using downward delivery

Question 15

What is an example of a gas collected using water displacement?

Answer 15

Hydrogen, oxygen, or carbon dioxide

Question 16

What is an example of a gas collected using upward delivery?

Answer 16

Ammonia

Question 17

What is an example of a gas collected using downward delivery?

Answer 17

Chlorine, hydrogen chloride, or sulfur dioxide

Question 18

Which drying agent is used for most gases but not ammonia?

Answer 18

Concentrated sulfuric acid

Question 19

Why must quicklime (calcium oxide) be freshly heated before use?

Answer 19

It absorbs moisture from the air and reacts with carbon dioxide

Question 20

In filtration, what is the substance left on the filter paper called?

Answer 20

Residue

Question 21

What is crystallization used for?

Answer 21

To obtain a pure solid from its saturated solution

Question 22

How is pure copper(II) sulfate obtained via crystallization?

Answer 22

By cooling a saturated copper(II) sulfate solution to form crystals

Question 23

What is simple distillation used for?

Answer 23

To separate a pure liquid from a solution

Question 24

How does fractional distillation differ from simple distillation?

Answer 24

It separates miscible liquids with different boiling points