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प्रश्न
The three important metalloids are.............................. and ..........................
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उत्तर
The three important metalloids are boron, silicon, and germanium.
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संबंधित प्रश्न
Classify the following into elements, compounds and mixtures:
- Sodium
- Soil
- Sugar solution
- Silver
- Calcium carbonate
- Tin
- Silicon
- Coal
- Air
- Soap
- Methane
- Carbon dioxide
- Blood
An inflated balloon full of air goes down slowly (becomes smaller and smaller slowly) even though the knot at the mouth of the balloon is airtight. And after a week all the air has escaped from the balloon. Explain how the air particles got out of the balloon.
Fill in the following blanks with suitable words :
An element is made up of only one kind of ........
What are the two types of pure substances? Give one example of each type.
Name a metal which has a low melting point.
If 25 mL of acetone is present in 150 mL of its aqueous solution, calculate the concentration of solution.
Which of the following will show Tyndall effect ? Why ?
- Salt solution
- Starch solution
- Milk
- Copper sulphate solution
Define Foam Give one example.
What do you understand by the statement " the solubility of copper sulphate in water at 20°C is 20.7 g" ?
Which one of the following is not a chemical change ?
One of the following represents the solution of solid in a solid. This one is :
What is fractional distillation ? What is the use of fractionating column in fractional distillation ?
Tincture of iodine is a mixture of two materials X and Y. The material Y has a property that its solid form can be converted directly into vapours on heating by a process called Z.
- What could X be ?
- What could Y be ?
- Name the process Z.
- Which process would you use to recover both the components X and Y from tincture of iodine ?
- Which process can be used to recover only component Y from tincture of iodine ?
Write a few lines on the blackboard with a chalk. Now observe the chalk. What changes do you see in the chalk?
Matter is made up of ______.
Define the term matter.
Name the metals that are used in jewellery.
Why wires cannot be drawn from materials such as stone or wood?
Evaporation does form bubbles.
The phenomenon of Evaporation takes place at the ______ of a liquid.
