chemistry MCQs - 10th class Chapter 07 Mcqs

1

What percentage of the human body is composed of water?

A

50%

B

60%

C

70%

D

80%

2

What percentage of the total water on Earth is potable, meaning fit for drinking?

A

2.1%

B

0.6%

C

0.2%

D

0.001%

3

At sea level, what is the boiling point of pure water?

A

90°C

B

100°C

C

110°C

D

120°C

4

At which temperature does water have its maximum density?

A

0°C

B

4°C

C

25°C

D

100°C

5

The specific heat capacity of water is approximately six times greater than that of rocks, at about __.

A

2.4 Jg⁻¹K⁻¹

B

3.8 Jg⁻¹K⁻¹

C

4.2 Jg⁻¹K⁻¹

D

5.0 Jg⁻¹K⁻¹

6

The process by which water rises up from the roots of plants to the leaves is known as what?

A

Surface Tension

B

Hydrogen Bonding

C

Polarity

D

Capillary action

7

Water is considered a universal solvent because of its polar nature and its exceptional __.

A

heat capacity

B

surface tension

C

hydrogen bonding ability

D

density

8

One molecule of water can form hydrogen bonds with a maximum of how many other water molecules?

A

Two

B

Three

C

Four

D

Five

9

Which type of compounds, such as alcohols and glucose, dissolve in water by forming hydrogen bonds?

A

Ionic compounds

B

Non-polar covalent compounds

C

Polar non-ionic compounds

D

Metallic compounds

10

Water that readily produces a good lather with soap is defined as __.

A

Hard water

B

Soft water

C

Heavy water

D

Mineral water

11

The hardness in water is primarily caused by the dissolved salts of which two elements?

A

Sodium and Potassium

B

Calcium and Magnesium

C

Iron and Copper

D

Chlorine and Fluorine

12

Temporary hardness of water is caused by the presence of which type of salts?

A

Sulphates

B

Chlorides

C

Nitrates

D

Bicarbonates

13

Permanent hardness of water is caused by the presence of sulphates and __ of calcium and magnesium.

A

Bicarbonates

B

Chlorides

C

Carbonates

D

Nitrates

14

Which simple physical method can be used to remove temporary hardness from water?

A

Filtration

B

Boiling

C

Freezing

D

Decantation

15

Clark's method, used for removing temporary hardness, involves the addition of a calculated amount of __.

A

Washing soda

B

Slaked lime

C

Baking soda

D

Chlorine

16

Permanent hardness in water can be removed by treating it with chemicals like __.

A

Vinegar

B

Hydrochloric acid

C

Washing soda

D

Caustic soda

17

What is the chemical name for the ion-exchanger sodium zeolite?

A

Sodium carbonate

B

Sodium chloride

C

Sodium aluminium silicate

D

Sodium sulphate

18

What is the correct chemical formula for washing soda?

A

NaHCO₃

B

Na₂SO₄

C

Na₂CO₃

D

NaOH

19

In the ion exchange process, a sodium zeolite resin exchanges its sodium ions for which ions in hard water?

A

K⁺ and Na⁺

B

Cl⁻ and SO₄²⁻

C

H⁺ and OH⁻

D

Ca²⁺ and Mg²⁺

20

The insoluble deposits of calcium and magnesium salts that form inside steam engines and boilers are called __.

A

Scum

B

Sediment

C

Scales

D

Rust

21

The waste materials discharged from various industrial units into water bodies are known as __.

A

Domestic sewage

B

Agricultural runoff

C

Industrial effluent

D

Solid waste

22

According to the text, acute poisoning from which heavy metal causes high blood pressure and kidney damage?

A

Lead

B

Mercury

C

Arsenic

D

Cadmium

23

Which heavy metal is specifically mentioned as causing neurological damage?

A

Cadmium

B

Lead

C

Mercury

D

Chromium

24

The presence of which salts in detergents leads to the rapid growth of algae in water bodies?

A

Sulphate salts

B

Chloride salts

C

Nitrate salts

D

Phosphate salts

25

The process where decaying plants consume dissolved oxygen from water is a direct result of pollution by __.

A

Heavy metals

B

Detergents and Fertilizers

C

Acids

D

Oil and greases

26

The process by which chemicals from fertilizers and pesticides seep into the groundwater is called __.

A

Run-off

B

Erosion

C

Leaching

D

Evaporation

27

Agricultural run-off pollutes surface water with phosphate and __ salts.

A

Sulphate

B

Nitrate

C

Chloride

D

Carbonate

28

The waterborne disease cholera is caused by which bacterium?

A

Escherichia coli

B

Salmonella typhi

C

Vibrio cholerae

D

Clostridium botulinum

29

The disease caused by the consumption of water with excess fluoride is known as __.

A

Hepatitis

B

Fluorosis

C

Typhoid

D

Jaundice

30

Which two types of Hepatitis virus can be transmitted through contaminated water?

A

Hepatitis B and C

B

Hepatitis A and E

C

Hepatitis C and D

D

Hepatitis B and D

31

Which disease is caused by a parasitic worm that infects the small intestine, often due to poor sanitary conditions?

A

Dysentery

B

Cholera

C

Hookworm

D

Cryptosporidiosis

32

Jaundice, which affects the liver, is caused by an excess of __ in the blood.

A

Red blood cells

B

White blood cells

C

Bile pigments

D

Calcium

33

What is the name of the process used to purify water by boiling it and then condensing the vapor?

A

Filtration

B

Sedimentation

C

Chlorination

D

Distillation

34

In the process of distillation, the pure water collected after condensation is called the __.

A

Residue

B

Filtrate

C

Precipitate

D

Distillate

35

What percentage of the world's water is stored in oceans?

A

79%

B

88%

C

97%

D

99%

36

According to the distribution chart, what percentage of the world's water is groundwater?

A

2.1%

B

0.6%

C

0.2%

D

0.001%

37

Which of the following non-polar substances does not dissolve in water?

A

Sugar

B

Salt

C

Alcohol

D

Benzene

38

The insoluble precipitate formed when soap reacts with the ions in hard water is called __.

A

Lather

B

Scum

C

Scale

D

Micelle

39

What chemical is commonly added to swimming pools for the purpose of disinfection?

A

Sodium

B

Fluoride

C

Chlorine

D

Calcium

40

When chlorine is added to water, it forms hydrochloric acid and __, both of which kill microorganisms.

A

Hypochlorous acid

B

Sulphuric acid

C

Nitric acid

D

Carbonic acid

41

An intestinal disease characterized by severe diarrhea, which may be accompanied by blood or mucous, is called __.

A

Gastro

B

Dysentery

C

Cholera

D

Typhoid

42

The polarity of a water molecule is due to the __ difference between oxygen and hydrogen atoms.

A

size

B

mass

C

electronegativity

D

isotope

43

Insoluble limestone (CaCO₃) can be dissolved in water by the presence of which gas?

A

Oxygen

B

Nitrogen

C

Carbon dioxide

D

Hydrogen

44

A sodium zeolite resin that has been fully used can be regenerated by flushing it with a concentrated solution of __.

A

CaSO₄

B

Mg(HCO₃)₂

C

Na₂CO₃

D

NaCl

45

What is identified as the main cause for the rapid spread of waterborne diseases?

A

Use of pesticides

B

Industrial pollution

C

Lack of proper sanitation

D

Climate change

46

Cryptosporidium, a cause of gastrointestinal illness, is what type of microorganism?

A

Bacterium

B

Virus

C

Fungus

D

Protozoa

47

Acute lead poisoning can cause dysfunction of the kidneys, liver, brain, and the __ system.

A

digestive

B

respiratory

C

circulatory

D

reproductive

48

A major environmental problem with some detergents is that they are __, meaning they cannot be broken down by microbes.

A

insoluble

B

non-biodegradable

C

volatile

D

acidic

49

What is the freezing point of pure water?

A

0°C

B

-4°C

C

4°C

D

10°C