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प्रश्न
What's the solution?
We need to rub salt on a corncob, but only salt crystals are available.
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उत्तर
We can pound salt crystals. Either we can use mortar pestle or we can also crush the crystals of salt in a grinder. Such powdered salt can be easily applied on the corncob.
संबंधित प्रश्न
Give one difference between atoms and molecules.
What elements do the following compounds contain ?
Sugar, Common salt
Classify the following into elements, compounds and mixtures :
arble, Air, Gold, Brass, Sand, Diamond, Graphite, Petroleum, Common salt, Sea-water, Chalk
What are (i) metals (ii) non-metals, and (iii) metalloids ? Give two examples each of metals, non-metals and metalloids.
Define the emulsion. Give one example.
Milk of Magnesia is :
Tincture of iodine has antiseptic properties. This solution is made by dissolving :
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 ?
The dyes present in fountain pen ink can be separated by the technique of :
There are three liquids A, B and C, all having different densities and different boiling points. Liquids A and C are organic in nature whereas liquid B is considered to be inorganic. When liquids A and B are put together in a container, they form a single layer. On the other hand, when, liquids B and C are mixed, they form two separate layers :
(a) Which process will you use to separate a mixture of A and B ?
(b) Which method will you use to separate a mixture of B and C ?
(c) Name the liquids which would behave like (i) A (ii) B and (iii) C.
