CHAPTER 8
Concepts of Metals and Non-Metals
EXERCISE
Q. 1. Darken the circle of correct answer
(i) Which of the following is not applicable to iron?
(a) sonorous
(b) dull
(c) malleable
(d) ductile
Ans. (b)
(ii) Which of the following metal reacts vigorously with water and
(a) magnesium
(b) copper
(c) sodium
(d) uranium
Ans. (c)
(iii) Which metal is commonly used to make food packaging materials as it is cheaper, and its thin sheets can be folded easily into any shape?
(a) Aluminium
(b) Copper
(c) Iron
(d) Gold
Ans. (a)
(iv) Which of the following is formed when the residue obtained on burning sulphur is mixed with water?
(a) sulphuric acid
(b) sulphurous acid
(c) sulphonic acid
(d) sulphur dioxide
Ans. (b)
(v) Bronze is an alloy of:
(a) copper and zinc
(b) copper and iron
(c) tin and zinc
(d) tin and copper
Ans. (d)
Q. 2. Fill up the blanks
(i) The non-metal that is used as an antiseptic in skin ointments is _________.
Ans. iodine
(ii) The metals present in bell metal are _________ and _________.
Ans. copper, tin
(iii) _________ is a metal which is liquid at room temperature.
Ans. mercury
(iv) A non-metal that is a good conductor of heat and electricity is _________.
Ans. graphite
(v) The property of a metal which is useful in making tin sheets is _________.
Ans. malleability
Q. 3. State with reasons whether the following statements are true or false.
(i) Aluminium and copper are examples of non-metals used for making utensils and statues.
Ans. False, because aluminium and copper are both metals.
(ii) Metals form oxides when combined with oxygen, the solution of which turns blue litmus paper to red.
Ans. False, because metallic oxides are basic in nature and they turn red litmus paper blue.
(iii) Oxygen is a non-metal essential for respiration.
Ans. True, because oxygen helps in respiration by reacting with food to release energy.
(iv) Copper vessels are used for boiling water because they are good conductors of electricity.
Ans. False, because copper vessels are used due to their good conductivity of heat.
(v) School bell is made of bell metal because this metal is ductile.
Ans. False, because bell metal is used for making bells due to its sonorous nature.
(vi) The black part present in hard pencil is a metal that conducts electricity.
Ans. False, because the black part of a pencil is graphite, which is a non-metal.
Q. 4. Match Column I with Column II
Column I
- Malleable
- Ductile
- Oxygen
- Copper
- Sulphur
- Diamond
- Sonority
- Iron
- Chlorine
- Platinum
Column II
(a) Can be transformed into wire
(b) For making crackers
(c) Give sheets on hammering
(d) For disinfecting water
(e) All living beings inhale during breathing
(f) For making electric wires
(g) For making rails
(h) Hardest non-metal
(i) Ringing of bells
(j) Used in making ornaments.
Ans. 1. (c), 2. (a), 3. (e), 4. (f), 5. (b), 6. (h), 7. (i), 8. (g), 9. (d), 10. (j)
Q. 5. Match the uses of metals and non-metals given in Column I with the jumbled names of metals and non-metals given in Column II.
Column I
(i) Used in electrical wiring
(ii) Most malleable and ductile
(iii) Living organisms cannot survive without it.
(iv) Plants grow healthy when fertilisers containing it are added to the soil
(v) Used in water purification
Column II
(a) ENXYGO
(b) NECOHIRL
(c) PEPORC
(d) TENGOINR
(e) OGDL
Ans. (i)-(c), (ii)-(e), (iii)-(a), (iv)-(d), (v)-(b)
Q. 6. Complete the following flowchart.
Q. 7. Explain the following terms
(i) Malleability
Ans. The property of metals by which they can be hammered into thin sheets is known as malleability.
(ii) Corrosion
Ans. Corrosion is the slow damage or wearing away of metals due to the action of air, water or chemicals.
(iii) Galvanization
Ans. The process of coating iron objects with a layer of zinc to prevent rusting is called galvanization.
Q. 8. Write the differences between metals and non-metals.
Ans.
| Metals | Non-metals |
|---|---|
| (a) They have lustre. | (a) They do not have lustre. |
| (b) They are malleable. | (b) They are not malleable. |
| (c) They are ductile. | (c) They are not ductile. |
| (d) They are sonorous. | (d) They are not sonorous. |
| (e) They are good conductors of heat and electricity. | (e) They are poor conductors of heat and electricity. |
Q. 9. Mention some applications of non-metals in everyday life.
Ans.
(i) Oxygen is used for breathing and respiration.
(ii) Carbon dioxide is used by plants during photosynthesis.
(iii) Diamond is used in making ornaments and jewellery.
(iv) Graphite is used for preparing pencil leads.
(v) Coal is commonly used as a fuel.
Q. 10.
You are provided with three iron nails, each dipped in oil, water and damped soil. Which iron nail will not rust, and why?
Ans. The iron nail kept in oil will not get rusted because the layer of oil prevents the nail from coming in contact with air and water. Both air and water are necessary for rusting.
Q. 11.
Metals are used for making electric wires. Can you mention two properties which make them suitable for this purpose?
Ans. Ductility and electrical conductivity.
Q. 12.
What properties of gold make it precious?
Ans. The following properties of gold make it precious:
(i) It is very lustrous.
(ii) It does not corrode.
(iii) It has limited availability.
Q. 13.
What product is formed when Magnesium reacts with water? What is the nature of the product? Is it acidic, basic or neutral?
Ans. When magnesium reacts with air, magnesium oxide is formed. It is basic in nature.
OLD Question Answer
The respiration of the organism
Exercise
1) After the end of the tour, the player usually takes a lot of time and effort.
Ans:- Our body needs more energy to lift or lift objects. But the supply of oxygen to generate this energy is limited. Therefore, I take Usha-Nishah food to avoid lack of oxygen in the body.
2) List the similarities and differences between aerobic and anaerobic respiration.
Ans- The food material is broken down in both aerobic and anaerobic respiration. The body is powered by both movement and breathing.
The difference between aerobic respiration and anaerobic respiration is that – aerobic respiration uses oxygen to break down food whereas anaerobic respiration does not use oxygen.
3) Why do I sneeze so often that I breathe too much dusty air?
Ans:- Our air contains different types of undigested particles. When I breathe, my nasal cavity holds these particles. Sometimes these particles pass through the nasal cavity and enter the soma. These granules stimulate the lining of the nasal cavity, resulting in our sneezing. Sneezing, this unfiltered particle-laden air passes through the lungs and dust-free clean air into our body.
4) He is a test taker. Soak 3/4 of each in water. Label them as A, B and C. Test ‘A’ is a snail, Test B is an aquatic plant and ‘C’ is a test plant, snails fill both. What will be the concentration of carbon dioxide in the test?
Ans: – (c) The amount of carbon-dioxide tested will be very high.
5) Mark the correct answer
A) Yogadi Vayu Somai Ahe of Paitachora Sarilai __________.
i) Haofaon ii) Flower
iii) Air pores iv) Bark
Ans: iii) Air holes.
b) During the exercise of wheat, our load is accumulated by __________.
(i) Carbon-dioxide (ii) Lactic acid
(iii) Air permeability (iv) Water
Answer: About lactic acid.
(c) Average range of normal pulse rates per minute during menstruation in an adult man.
i) 9-12 i) 15-18
i i i) 21-28 iv) 30-33
Answer: ii) 15-18.
D) Kamihara during Nisha
i) Accelerates outwards i ) Accelerates downwards
i i i) Moves upward iv) Does not produce any kind of load
Answer: ii) Accelerates downward.
6) Combine Pillar 2 topics with Pillar 1
Pillar 1 Pillar 2
a) East i) Kechu
b) Diaphragm ii) Flower
c) Bark iii) Elk’hall
d) Leaf iv) Thoracic cavity
e) fish v) leaves
f) Vekuli vi) Sighing and barking
vii) Respiratory tract
Answer: (a) Ishta iii) Elk’hal
(b) Diaphragm iv) Thoracic cavity
(c) Bark i) Earthworm
(d) Leaf v) Leaves
(e) Fish ii) Flowers
(f) Vekuli vi) Haofaon and Bark
7) Write “Shu” if the quote is pure and “A” if it is impure:
i) During exercise, the person’s heart rate decreases. (Shu\n)
Answer: A
ii) Plants do photosynthesis only during the day and respiration only during the night. (Su \ Non)
Answer: Shu
i i i) Veculia performs the function of respiration by means of sphincter bark and snoring. (Shu\A)
Answer: Shu
iv) Fishes have gasps for respiration. (Shu\A)
Answer: A
v) The size of the thoracic cavity increases during menstruation. (Shu\A)
Answer: Shu
8) Spellings of different words related to the breath of life are hidden under the square. Discuss the vocabulary of breathing technique. Below are the vocabulary words.
i) Trachea of moths.
Answer: Trachea.
ii) Chest cavity and bone structure.
Answer: Kamihar.
iii) Muscular floor of thoracic cavity.
Answer: Middle.
iv) The surface of the plate is divided into small holes.
Answer: Newspaper.
v) Thaka Saru Bindha on the wings or sides of the moth’s body.
Answer: Air vents.
vi) Human respiratory system.
Answer: Sigh
vii) In which point I take Ushah-Nishah.
Answer: Nasal cavity.
viii) Tracheal moths
Answer: Paitachora
ix) Such mortal beings
Answer: Yes
9) Mountain climbers carry buckets of oxygen because,
a) Wind netha at altitudes above 5 km.
b) The air requirement of a person is less than the ground level.
c) Heat of the air rises to the surface.
d) Air pressure on the earth’s surface.
Ans: (b) The air required by this person is less than the ground surface.
এই Post টো Update কৰাত সহায় কৰিব বিচাৰে নেকি?
ইয়াত কিবা ভুল, অসম্পূৰ্ণ তথ্য বা নতুন তথ্য থাকিলে আপুনি এটা উন্নত version প্ৰস্তুত কৰিব পাৰে। Live Post তৎক্ষণাৎ সলনি নহ'ব।
Update This Post