Learnwell science chapter Metals and Non metal Questions answer class 8

CBSE/NCERT_Metals and Non Metal Questions answer class 8

Very short answer questions

1. What is malleability?

Ans: Metal can be beaten into thin sheet. this properties oh metal is called malleability. Gold is the most malleable metal.

2. Name a metal exist in liquid state

Ans: Mercury is a metal that exist in liquid state at room temperature.

3. Which metal is the best conductor of electricity?

Ans: Silver

4. Name the metals ha highest melting pint.

Ans: Tungsten

5. Name the lightest metal

Ans: Lithium

6. Which is the only non metal that can conduct electricity?

Ans: Graphite

7. Name the two non metals that are lustrous

Ans : Graphite and iodine

8. What are allotropes?

Ans: Two or more form of same element which differ in properties. Diamond and graphite are two allotropes of carbon

Write true and false

1. Metals react with oxygen to form oxide: False

Metals react with oxygen to form metallic oxide

2. Magnesium and aluminium react quickly with oxygen: False

Sodium and potassium react quickly with oxygen so they are stored in kerosene oil

3. Metals react with water to form metal oxide: True

4. All metal react with bases: False

Most of the metals do not react with bases. Only Zinc, lead and aluminium only react with strong bases like NaOH and KOH

5. Non Metal react with air at room temperature: False

Non Metal reacts with air on heating

6. Non metal do not react with water: True

Name the metals and Non metal used for:
1. Filling electric bulb – Argon

2. Constructing bridge: - Iron

3. Making electric wire: - copper and aluminium

4. Making foil for wrapping food: - Aluminium

5. Making pencil leads: - Graphite

6. Making x-ray shield and bullets: - lead

7. Water purification: Chlorine

8. Filled in electric tube and glow sign: - Neon

9. Filled in gas balloon: - Helium

10. Preserve blood and other donated organ: - Nitrogen

Answer these question:

1. Why are musical instrument and bell made up of metal?

Ans: Musical instrument and bell are made up of metal because metal produce ringing sound when struck by something.

2. Why are electric wire made up of copper?

Ans: Electric wire is made up of copper because copper is god conductors of electricity.

3. Why sodium and potassium stored in kerosene?

Ans: Sodium and potassium react quickly with oxygen at room temperature so they are stored in kerosene oil

4. Why is phosphorous stored under water?

Ans: phosphorous rapidly burn in air at room temperature so it is stored under water for safety.

5. Why silver and gold do not react with hydrochloric acid?

Ans: This is because silver and gold are less reactive than hydrogen.

6. Why is graphite not used for making electric cable?

This is because graphite is a non metal that cannot drawn into wire.

For rest of the questions visit: Metals and Non metal questions with solution

Comments

CBSE ADDA :By Jsunil Sir : Your Ultimate Destination for CBSE Exam Preparation and Academic Insights

Class 10 Chapter 02 Acid Bases and Salts NCERT Activity Explanation

NCERT Activity Chapter 02 Acid Bases and Salt Class 10 Chemistry Activity 2.1 Indicator Acid Base Red litmus No Change Blue Blue Litmus Red No change Phenolphthalein Colourless Pink Methyl Orange Pink Yellow Indictors are substance which change colour in acidic or basic media. Activity 2.2 There are some substances whose odour changes in in acidic or basic media. These are called olfactory indicators. Like onion vanilla, onion and clove. These changes smell in basic solution. Activity 2.3 Take about 5 mL of dilute sulphuric acid in a test tube and add few pieces of zinc granules to it. => You will observe bubbles of hydrogen gas on the surface of zinc granules. Zn + H2SO4 --> ZnSO4 + H2 => Pass the Hydrogen gas through the soap solution. Bubbles formed in the soap solution as Hydrogen gas it does not get d...

CBSE I NCERT 10th Numerical Problem solved Reflection and reflection of light

Q. 1. A concave mirror of focal length 20cm is placed 50 cm from a wall. How far from the wall an object be placed to form its real image on the wall? Solution: V= -50 cm F= -20cm From mirror formula 1/u = 1/f – 1/v = -1/20+ 1/50 = - 3/100 U = - 33.3 cm Therefore, the distance of the object from the wall x = 50 – u X = 50 – 33.3 = 16.7 cm. Q.2. An object is placed at a distance of 40cm from a concave mirror of focal length 15cm. If the object is displaced through a distance of 20 cm towards the mirror, By how much distance is the image displaced? Answer: Here f = - 15 cm, u = - 40 cm Now 1/f = 1/u + 1/v Then 1/v = 1/f – 1/u Or V= uf/u-f =( - 40 x -15)/25 = -24 cm Then object is displaced towards the mirror let u1 be the distance object from the Mirror in its new position. Then u1 = -(40-20) = -20cm If the image is formed at a distance u1 from the mirror then v1 = u1f/u1-f = -20X-15/-20+15 = -60 cm. = - 20 x-15/-20+15 = -60 ...

Class 10 Metal and Non MetalsChapter 03 NCERT Activity Solutions

X Class 10 NCERT Activity Explanation Class 10 Metals and Non Metals Activity 3.1 Page No. 37 Take samples of iron, copper, aluminium and magnesium. Note the appearance of each sample. They have a shining surface. Clean the surface of each sample by rubbing them with sand paper and note their appearance again. They become more shiny. => Freshly cut Metal have shiny surface Activity 3.2 Page No. 37 Take small pieces of iron, copper, aluminium, and magnesium. Try to cut these metals with a sharp knife and note your observations. They are very hard to cut. Hold a piece of sodium metal with a pair of tongs and try to cut it with a knife. Sodium can be cut easily with knife. Hence K and Na are soft metal cut with knife Activity 3.3 Page No. 38 Take pieces of iron, zinc, lead and copper try to strike it four or five times with a hammer. These metals are beaten into thin sheet on hammering. This property of metal is called malleability and metals are called malleable. Activity 3.4 Page ...

Living science ratna sagar class 6 solutions

Ratna sagar living science 6 answers by jsunil. Class6 Living science solution Term-1 Living Science Solution chapter-1 Source of food Download File Living Science Solution chapter-2 Component of food Download File Living Science Solution chapter-3 Fibre to fabric Download File Living Science Sol ch-4 Sorting of material into group Download File Living Science Soln ch-5 Separation of substance Download File Living Science Solution chapter-6 Change around Us Download File Living Science Solution ch-7 Living and Non Living Download File Living Science Solution ch-8 Getting to Know Plants Download File Living Science Sol ch-9 The Body and Its movements Download File Visit given link for full answer Class6 Living science solution Term-II

Electricity numerical for class 10 CBSE Trend Setter 50 Problems

1. The current passing through a room heater has been halved. What will happen to the heat produced by it? 2. An electric iron of resistance 20 ohm draws a current of 5 amperes. Calculate the heat produced in 30 seconds. 3. An electric heater of resistance 8 ohm takes a current of 15 A from the mains supply line. Calculate the rate at which heat is developed in the heater. 4. A resistance of 40 ohms and one of 60 ohms are arranged in series across 220 volt supply. Find the heat in joules produced by this combination in half a minute. 5. A resistance of 25 ohm is connected to a 12 V battery. Calculate the heat energy in joules generated per minute. 6. 100 joules of heat is produced per second in a 4 ohm resistor. What is the potential difference across the resistor? 7. An electric iron is connected to the mains power supply of 220 V. When the electric iron is adjusted at minimum heating’ it consumes a power of 360 W but at ‘maximum heating’ it takes a power of 840 W. Ca...

CBSE ADDA

Search This Blog