General Science 6th Class Chapter 6 Elements and Compounds Solved Exercise

General Science

6th Class

Chapter 6

Elements and Compounds

Questions

6.1 Encircle the correct option.

1. Which one of the following is a metallic element?

a. hydrogen        b. helium        c. lithium        d. carbon

2. Which one of the following is a non-metallic element?

a. iron        b. aluminium        c. beryllium        d. oxygen

3. Which one of the following is a metalloid element?

a. gold        b. boron        c. silver        d. nitrogen

4. Choose an atom which can exist independently at room temperature?

a. Cu        b. Na        c. O        d. Ne

5. How many hydrogen atoms are present in 1 molecule of ammonia?

a. 1        b. 2        c. 3        d. 4

6. How many atoms are present in one molecule of helium?

a. 1        b. 2        c. 3        d. 4

7. C₆H₁₂O₆ is the formula of glucose. How many oxygen atoms are there in one molecule of glucose?

a. 3        b. 6        c. 9        d. 12

8. Which one of the following is an element?

a. O₃        b. CO₂        c. CH₄        d. H₂O

9. Number of neutrons in helium atom:

a. 1        b. 2        c. 3        d. 4

10. This picture indicates the structure of:

a. an atom        b. an element        c. a compound        d. none of these

11. Water, carbon dioxide, ammonia and methane are examples of:

a. atoms        b. elements        c. compounds        d. mixtures

12. Hydrogen, helium, carbon, nitrogen and oxygen are examples of:

a. atoms        b. elements        c. compounds        d. mixtures

6.2 Write short answer.

1. Define element.

Ans.

An element is a substance which consist of only one kind of atoms. It is simplest form of matter.

2. Write the names and symbols of any two metals.

Ans.

Magnesium Mg and Iron Fe.

3. Write the names and symbols of any four non-metals.

Ans.

Hydrogen H, Nitrogen N, Neon Ne, Oxygen O.

4. Write names and symbols of any three noble gases.

Ans.

Neon Ne, Argon Ar, Krypton Kr.

5. Write the names and formulae of any five compounds.

Ans.

Ammonia NH3, Sodium chloride NaCl, Glucose C6H12O6, Methane CH4, Carbon dioxide CO2.

General Science 6th Class Chapter 5 Matter as Particles Solved Exercise

General Science

6th Class

Chapter 5

Matter as Particles

Questions

5.1 Encircle the correct option.

1. There are strong forces of attraction between the particles of:

a. solids        b. liquids        c. gases        d. all of these

2. Solid and liquid objects cannot be compressed easily as their particles are:

a. closely packed        b. loosely packed

c. lacking spaces among them        d. scattered irregularly

3. The process of changing gas into liquid:

a. melting        b. evaporation        c. freezing        d. condensation

4. Changing of substance directly from solid state to gaseous state on heating is termed as:

a. boiling        b. sublimation        c. melting        d. diffusion

5. Materials that don't take the shape of the container:

a. solids        b. liquids        c. gases        d. all of these

6. When a gas condenses, it becomes a:

a. solid        b. liquid        c. crystal        d. another gas

7. When a solid object is heated, its particles begin to:

a. vibrate fast        b. vibrate slowly        c. stop vibrating        d. move freely

8. Boiling point of water is:

a. 0˚ C       b. 0˚ F        c. 100˚ C        d. 100˚ F

9. Movement of particles from an area where they are more to an area where they are less:

a. boiling        b. evaporation        c. diffusion        d. sublimation

10. Which of the following is opposite to boiling?

a. evaporation        b. freezing        c. melting        d. condensation

5.2 Give short answers.

1. How can we change the physical state of matter?

Ans.

Physical state of matter can be changed by the processes of melting, boiling, condensation and freezing.

2. How do liquids differ from gases?

Ans.

Liquids differ from gases as in liquids, the particles are present very close to one another and have attractive forces among them. In gases, particles are away from each other and have almost no attractive forces present among them.

3. How do solids differ from liquids with regard to particles arrangement?

Ans.

In solids, particles have an orderly arrangement where they are present tightly packed with each other, while in liquids, the particles are present very close to one another but they are not regularly arranged.

4. A liquid on cooling is converted into its solid state. What will happen to a solid when it is cooled?

Ans.

Cooling a solid decreases the motion of its particles. A decrease in motion of particles allow the attraction between the particles to bring them a more close together.

5. Write down the names of five liquids and five gases which you know.

Ans.

Liquids: Water, Milk, Blood, Gasoline, Mercury.

Gases: Natural gas, oxygen, nitrogen, Helium, carbon dioxide.

General Science 6th Class Chapter 4 Human Digestive System Solved Exercise

General Science

6th Class

Chapter 4

Human Digestive System

Questions

4.1 Encircle the correct option.

1. A part of the digestive system which is not in correct with food is:

a. small intestine        b. stomach        c. liver        d. large intestine

2. In humans, most of digestion takes place in:

a. mouth        b. oesophagus        c. stomach        d. small intestine

3. Saliva is produced in:

a. oral cavity        b. oesophagus        c. stomach        d. small intestine

4. The food digested by the enzyme "sucrase" belongs to nutrients group:

a. carbohydrates        b. fats        c. oils        d. proteins

5. The muscular tube leading from oral cavity to stomach:

a. small intestine        b. large intestine        c. oesophagus        d. bile duct

6. Germs present in food are killed in stomach by:

a. hydrochloric acid        b. citric acid        c. carbonic acid        d. none of these

7. Digestive enzymes convert starch into:

a. fatty acids        b. vitamins        c. minerals        d. simple sugar

8. Proteins are digested into:

a. fatty acids        b. amino acids        c. glycerol        d. glucose

9. Digested food is absorbed into blood through the walls of:

a. villi        b. large intestine        c. stomach        d. bile duct

10. Water and salts from indigested food are absorbed into blood through walls of:

a. small intestine        b. large intestine        c. villi        d. gallbladder

4.3 Give short answer.

1. Define digestion.

Ans.

The process during which large and complex molecules are broken down into such smaller pieces which pass across walls of small intestine and absorb into the blood is called digestion.

2. How is chewing important in human digestive system?

Ans.

Chewing activity mixes saliva in the food to make it soft.

3. Name the liquid which is secreted by salivary glands.

Ans.

Salivary glands secrete saliva.

4. Describe the role of oesophagus in human digestive system.

Ans.

Oesophagus is a narrow muscular tube through which food passes from oral cavity to the stomach.

5. Why do carbohydrates, fats and proteins need to be broken down into smaller molecules?

Ans.

The food we eat consist of large and complex molecules of carbohydrates, fats and proteins, these complex food molecules cannot pass across wall of small intestine for absorption in blood.

6. What are the products of digestion of carbohydrates, proteins and fats?

Ans.

Carbohydrates from glucose, protein gives amino acids and fats release fatty acid and glycerol.

7. What structures secrete enzymes necessary for digestion in man?

Ans.

Salivary glands, gastric glands, liver and pancreas are structures secrete enzymes necessary for digestion in man.

8. How are villi important for absorption?

Ans.

The digested food is absorbed through the wall of villi and passes into the blood streams.

9. How is large intestine important in digestive system of man?

Ans.

Some water and mineral salts are also absorbed into the blood through the walls of the large intestine.

10. Write the functions of gall bladder.

Ans.

Gall bladder stores bile.

General Science 6th Class Chapter 3 Balanced Diet Solved Exercise

General Science

6th Class

Chapter 3

Balanced Diet

Questions

3.1 Encircle the correct option.

1. An immediate source of energy for our body is:

a. mango        b. chicken        c. mushroom        d. meat

2. Food rich in proteins is:

a. potato        b. grapes        c. fish        d. rice

3. Which food is best for providing fats?

a. fruits        b. butter        c. vegetables        d. bread

4. Food rich in carbohydrates is:

a. corn oil        b. beef        c. egg        d. starch

5. Source of vitamin A is:

a. table salt        b. carrot        c. mustard oil        d. sugar

6. Source of starch is:

a. egg        b. meat        c. fish        d. potato

7. Vegetable oils are included in the food group:

a. carbohydrates        b. proteins        c. fats        d. vitamins

8. Balanced diet for an infant is:

a. fruit        b. milk        c. vegetable        d. egg

9. Which vitamin makes the bones strong?

a. Vitamin A        b. Vitamin B        c. Vitamin C        d. Vitamin D

10. Iron is a:

a. vitamin        b. mineral        c. carbohydrate        d. protein

3.2 Give short answers.

1. Why do we need food?

Ans.

Food provide us energy and nutrients needed for vital processes like growth, repair, reproduction and protection.

2. Name major food groups.

Ans.

Food is classified into following major groups.

• Carbohydrates
• Proteins
• Fats
• Vitamins
• Minerals

3. Name sources of vitamin A.

Ans.

Carrot, cod liver etc. are sources of vitamin A.

4. Enlist the sources of vitamin C and D.

Ans.

Vitamin C: Citrus fruits, orange, guava, broccoli, strawberry etc. are sources of vitamin C.

Vitamin D: Milk, cod liver oil and soybean are sources of vitamin D.

5. List sources of minerals.

Ans.

Minerals are found in milk, meat, grains, vegetables, fruits, eggs, fish, etc.

6. What is unbalanced diet?

Ans.

A diet lacking one or more essential components of food needed by a person is called unbalanced diet.

7. Is table salt a mineral?

Ans.

Table salt is mineral due to presence of sodium in it.

General Science 6th Class Chapter 2 Reproduction in Plants Solved Exercise

General Science

6th Class

Chapter 2

Reproduction in Plants

Questions

2.1 Encircle the correct option.

1. Pollination is the transfer of:

a. sepal        b. stamen        c. pollen grain        d. ovum

2. Zygote is formed as a result of:

a. self-pollination        b. cross pollination        c. fertilization        d. double fertilization

3. Zygote develops into:

a. embryo        b. embryo sac        c. endosperm        d. ovule

4. Asexual reproduction in which stem of a plant is buried in soil near the present plant:

a. layering        b. budding        c. cutting        d. grafting

5. The organ of a plant which takes part in sexual reproduction:

a. root        b. stem        c. leaf        d. flower

6. The structure which is helpful to carry sperms to the ovary:

a. pollen tube        b. stigma        c. style        d. ovary

7. Which is the example of natural vegetative propagation?

a. runners' growth into new plant        b. budding        c. cutting        d. grafting

8. Production of new plant from underground stem is an example of:

a. sexual reproduction        b. asexual reproduction

c. self-pollination        d. cross pollination

9. Fusion of a sperm with two polar nuclei forms:

a. zygote        b. embryo        c. ovum        d. endosperm

10. Male reproductive cell:

a. egg        b. sperm        c. neuron        d. zygote

2.2 Differentiate between:

1. Sexual reproduction and asexual reproduction

Ans.

The microorg

2. Self-pollination and cross pollination

Ans.

3. Pollen grain and ovule

Ans.

4. Fertilization and double fertilization

Ans.

5. Budding and grafting

Ans.

6. Scion and stock

Ans.

2.3 Give short answers.

1. Name three self -pollinated plants.

Ans.

Pea, cotton and tomato are self-pollinated plants.

2. Name three cross pollinated plants.

Ans.

Maize, Papaya and rose are cross pollinated plants.

3. Name the underground stems that undergo natural vegetative propagation.

Ans.

Underground stems like bulb and tuber are the example of natural vegetative propagation in plants.

4. What are runners?

Ans.

In some plants such as strawberry and grasses, stems are spread horizontally above the ground. These stems are called runners. Runners have nodes where buds are present. New plants grow from these buds.

5. Name different parts of the carpel (female reproductive structure).

Ans.

Stigma, style and ovary are parts of carpel (female reproduction structure).

General Science 6th Class Chapter 1 Cellular Organization Solved Exercise

 General Science

6th Class

Chapter 1

Cellular Organization

Questions

1.1 Encircle the correct option.

1. An animal cell has:

a. single vacuole        b. two vacuoles        c. many vacuoles        d. no vacuole

2. Mitochondria are the cell organelles that play role in:

a. protein synthesis        b. food production

c. producing energy from food        d. removing waste products

3. Chromosomes are present in:

a. chloroplast        b. nucleus        c. cell wall        d. vacuole

4. Cell membrane is composed of:

a. proteins and lipids        b. cellulose and lipids

c. cellulose and proteins        d. lipids

5. Chlorophyll is a pigment whose colour is:

a. red        b. blue        c. yellow        d. green

6. Human skin is made of:

a. muscle tissue        b. blood tissue        c. epidermal tissue        d. epithelial tissue

7. Oxygen is carried from lungs and supplied to the whole body by:

a. white blood cells        b. red blood cells        c. platelets        d. bone cells

8. Site for respiration in a cell is:

a. nucleus        b. endoplasmic reticulum        c. chloroplast        d. mitochondria

9. Water is conducted from roots to leaves by:

a. xylem        b. phloem        c. epidermis        d. mesophyll

10. Kidneys perform functions related to:

a. digestive system        b. breathing system        c. circulatory system        d. excretory system

1.2 Give short answers.

1. Name the cell organelle that controls the whole cell activity.

Ans.

Nucleus controls the whole body activities.

2. Write the function of blood in human body.

Ans.

Blood circulates throughout the body to transport materials from one past of the body to another.

3. Enlist the organs involved in blood circulatory system in man.

Ans.

Following organs are involved in blood circulatory system. Heart, arteries, veins and capillaries.

4. Name the red coloured pigment present in red blood cells.

Ans.

Haemoglobin is present in red blood cells.

1.3 Differentiate between:

1. Animal cell and plant cell

Ans.

Animal cell

i. It has no cell wall.

ii. It has many small vacuoles.

iii. Animal cell has no chloroplast.

Plant cell

i. It has a cell wall.

ii. It has a single large vacuole.

iii. It has chloroplast.

2. Cytoplasm and nucleoplasm

Ans.

Cytoplasm

The jelly like material present inside the cell membrane is known as cytoplasm. Most of the cell functions take place here.

Nucleoplasm

The material inside the nucleus is called nucleolus plasma. It consists on thread like structure.

3. Xylem and phloem

Ans.

4. Epidermal tissue and epithelial tissue

Ans.

5. Root system and shoot system in plants

Ans.

General Science 8th Class Chapter 5 Periodic Table Solved Exercise

 General Science

8th Class

Chapter 5

Periodic Table

Questions

1. Encircle the correct option.

(i) An element of the third period in the Periodic Table:

a. H        b. P        c. He        d. Li

(ii) Mg belongs to the period of the Periodic Table:

a. 1st        b. 2nd        c. 3rd        d. 4th

(iii) An alkali metal:

a. F        b. Be        c. Al        d. Na

(iv) Ne belongs to:

a. nitrogen family        b. fluorine family        c. noble gases        d. alkaline earth metals

(v) An element of group 17 of the Periodic Table:

a. Cl        b. Ar        c. S        d. Si 

(vi) Atomic number of the element at fourth position in second period:

a. 4        b.5        c. 6        d. 7

(vii) How many periods are there in the Periodic Table?

a. Five        b. Six        c. Seven        d. Eight

(viii) A metal:

a. Cu        b. C        c. Cl        d. Ne

(ix) A non-metal:

a. H        b. Na        c. Li        d. Be

(x) An atom containing two electrons:

a. H        b. He        c. Li        d. Be

2 Write short answers.

(i) What is meant by a period in the Periodic Table?

Ans.

The horizontal rows of elements in the Periodic Table are called "Periods".

(ii) What is meant by a group of the Periodic Table?

Ans.

The vertical columns in the Periodic Table are called "Groups".

(iii) Define element.

Ans.

An element is a substance, which cannot split into two or more substances by ordinary chemical changes.

(iv) What do you mean by an atomic number?

Ans.

The number of protons present in an atom of an element is called atomic number (Z) of that element.

(v) How many electrons are there in the valence shell of H?

Ans.

There is one electron in the valence shell of H.