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प्रश्न
Honey is more viscous than water. Can you suggest why?
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उत्तर
Honey is more viscous than water because inter-molecular force of attraction between honey particles is more than that of water molecules.
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संबंधित प्रश्न
Name the terms for the change of a solid into liquid.
All kinds of matter
Classify the following into elements, compounds and mixtures:
- Sodium
- Soil
- Sugar solution
- Silver
- Calcium carbonate
- Tin
- Silicon
- Coal
- Air
- Soap
- Methane
- Carbon dioxide
- Blood
State two characteristics of matter demonstrated by Brownian motion.
Explain why steel is used to make railway lines.
Explain why, osmosis can be considered to be a special kind of diffusion. Classify the following into
(i) osmosis, and (ii) diffusion :
- swelling up of a raisin on keeping in water
- spreading of virus on sneezing
- earthworm dying on coming in contact with common salt
- shrinking of grapes kept in thick sugar syrup
- preserving of pickles in salt
- spreading of smell of cake being baked in the kitchen
- aquatic animals using oxygen dissolved in water during respiration
Iron powder and sulphur powder were mixed together and divided into two parts A and B. When part A was heated strongly over a burner, then a substance C was formed. The part B was, however, not heated at all. When dilute hydrochloric acid was added to substance C, then gas D was evolved and when dilute hydrochloric acid was added to part B then gas E was evolved.
- What type of substance is B ?
- What type of substance is C ?
- Name the gas (i) D, and (ii) E ?
- State one characteristic property of gas D.
- Write one test to identify gas E.
How will you differentiate between a suspension and a colloid ?
What is a colloid ? Give two examples of colloids (or colloidal solutions)
How would you prepare a saturated solution of sodium chloride in water at 25°C ? What will happen if this solution is cooled to 10°C ?
100 mL of water at room temperature of 25°C is taken in a beaker and a little of solid S is dissolved in it by stirring to obtain a solution X. More and more of solid S is added to the solution with constant stirring, while keeping the temperature of solution constant at 30°C. After some time it is observed that no more solid dissolves in water and at the same time some solid is also left undissolved at the bottom of the beaker.
- The contents of beaker are filtered through a filter paper to obtain solution Y in the form of a filtrate.
- What name is given to solutions like X ?
- What name is given to solutions like Y ?
- What will you observe if the solution Y at 30°C is cooled down to 10°C by keeping the beaker in crushed ice ? Why ?
- What term is used to denote the amount of solid dissolved in 100 grams of water in a solution lie Y ?
State whether the following statement are true or false :
Salt and water can be recovered from an aqueous salt solution by the process of evaporation.
Name the source from which nitrogen and oxygen are obtained on a large scale.
Name the process which can be used to purify an impure sample of copper sulphate.
One of the following does not undergo sublimation. This one is :
What difference in the properties of common salt and sand would enable you to separate a mixture of these two substances ?
______ is so hard that it can scratch glass.
Evaporation does form bubbles.
Compressibility of solids: ______.
Define the term matter.
