Advertisements
Advertisements
प्रश्न
Give reasons
Graphite is used in the leads of pencils
Advertisements
उत्तर
Graphite turns paper black that is why it is used in the leads of pencils.
APPEARS IN
संबंधित प्रश्न
What happens when Dilute sulphuric acid is poured on a copper plate?
Write word equations of the reactions involved.
What happens when Iron nails are placed in copper sulphate solution?
Write word equations of the reactions involved.
The atomic number of an element Y is 16.
(a) What must an atom of Y do to achieve the nearest inert gas electron arrangement?
(b) Which inert gas is nearest to Y?
What is a thermite reaction? Explain with the help of an equation. State one use of this reaction.
What is an alloy? Give two examples of alloys.
Mention two uses of the following metals and non-metals
Aluminium
Mention two uses of the following metals and non-metals
Oxygen
Fill in the blank
A metal that gives dazzling effect to crackers when they explode is ______
Write ‘true’ or ‘false’ for the following statement.
Iodine acts as an antiseptic in the form of a tincture of iodine.
Fill in the blank spaces by choosing the correct words from the given list.
List: amalgam, chlorine, gallium, sodium chloride, silver chloride
A solution of a metal in mercury is called ________
Statements given below are incorrect. Write the correct statements :
Aluminium is best conductor of electricity.
Take an element from an alkali metal and one from an alkaline earth metal and write an equation for their action with:
Sulphuric acid
Write name.
The nonmetal having electrical conductivity.
Name the following:
A metal used in flexible pipes.
Complete the following flowchart.
Complete the following flow chart.
Which one of the following is an example for a metal?
Give reasons for the following.
- Aluminum foils are used to wrap food items.
- Immersion rods for heating liquids are made up of metallic substances.
- Sodium and potassium are stored in kerosene.
- Mercury is used in thermometers.
Match the following
| i. | Silica | a. | Caustic potash |
| ii. | Potassium hydroxide | b. | Sand |
| iii. | Sodium hydroxide | c. | Calamine |
| iv. | Zinc carbonate | d. | Caustic soda |
