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प्रश्न
What is an amalgam?
उत्तर
Amalgam is an alloy of mercury with one or more metals. Sodium along with liquid mercury is known as sodium amalgam. Amalgam of mercury with tin, silver and zinc is widely used in dental filling.
संबंधित प्रश्न
What happens when Iron nails are placed in copper sulphate solution?
Write word equations of the reactions involved.
Saloni took a piece of burning charcoal and collected the gas evolved in a test tube.
(a) How will she find the nature of the gas?
(b) Write down word equations of all the reactions taking place in this process.
State one use of Silver.
Fill in the following blank with suitable word:
The alloy in which one of the metals is mercury is called an ...............
What is an alloy? How is an alloy made?
Give two uses of Germanium
Fill in the blank
_______ is a soft metal.
Statements given below are incorrect. Write the correct statements :
Aluminium is best conductor of electricity.
Write ‘True’ or ‘False’ in front of following statement.
Magnesium is used in making light weight alloys of aluminium.
Take an element from an alkali metal and one from an alkaline earth metal and write an equation for their action with:
Hydrochloric acid,
Write name.
The oxide that forms salt and water by reacting with both acid and base.
Give reasons for the following:
Most metals conduct electricity well.
Give a reason why a green deposit is seen on the surface of an article of copper
Aluminium: _______: gold : : electric insulator
Complete the following flowchart.
A is a reddish-brown metal, which combines with O2 at < 1370 K gives B, a black coloured compound. At a temperature > 1370 K, A gives C which is red in colour. Find A, B, and C with reaction.
Which of the following metals are obtained by electrolysis of their chlorides in molten state?
- Na
- Ca
- Fe
- Cu
Why are bells made of metals?
Which of the following metals can displace the other two metals from their salt solutions?
| Zinc | iron | copper |
Match the following
| i. | Softest metal | a. | Copper |
| ii. | Hardest metal | b. | Sodium |
| iii. | Hardest non–metal | c. | Osmium |
| iv. | Ductility | d. | Diamond |
