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प्रश्न
Complete and balance the following chemical equations
Na + H2 O →
उत्तर
\[\ce{Na + H2O→2NaOH + H2↑}\]
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संबंधित प्रश्न
How do the following help in bringing about a chemical change?
light.
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`"H"_2"S"` + `"CI"_2` `→`
Define precipitation.
FILL IN THE BLANK
Positively charged ions are called ........
TRUE \ FALSE
Copper can displace iron from iron sulphate.
Fill in the blank.
Melting of ice is a _______ change.
Fill in the blank:
The substances formed as a result of a chemical reaction are called _______
Complete the statement by filling the gaps using appropriate term from the terms given in the bracket.
(slow, coloured, arrow, fast, smell, milky, physical, product, chemical, reactant, covalent, ionic, octet, duplet, exchange, sharing, equality sign)
The spoiling of food is a chemical change which is recognized from the generation of certain ______ due to it.
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Electron ______ is complete in each hydrogen in a hydrogen molecule.
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Light
Give an example of a reaction where the following are involved
Catalyst
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What do you observe? When
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\[\ce{Pb(NO3)2 ->[\Delta]}\]
What is observed in performing the following :
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| Litmus test | ||||
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What do you observe when CO2 is passed through lime water first and then a little in excess.
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A coloured substance which leaves on strong heating a black residue and evolves two colourless gases one of which is acidic and the other neutral.
A chemical reaction is often accompanied by external indications or characteristics.
Select the correct answer from the options given below:
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Name the solid residual product formed reaction and state its colour during – thermal decomposition of the following substance.
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The water we drink is a combination of hydrogen and oxygen.
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Can you change rust back into iron by some simple method?
The chemical name of baking soda is sodium bicarbonate.
Write a note on the following:
Curdling of milk
Write the characteristics of chemical change.
Photosynthesis is a chemical charge. Justify your answer.
______ is the chemical name of slaked lime.
______ is the chemical name of limestone.
