Advertisements
Advertisements
प्रश्न
Complete and balance the following reaction:
\[\ce{Pb(NO3)2 ->[\Delta]}\]
उत्तर
\[\ce{Pb(NO3)2 ->[\Delta] 2PbO + 4NO2 + O2}\]
APPEARS IN
संबंधित प्रश्न
What are (i) positive catalysts and (ii) negative catalysts? Support your answer with one example for each of them.
Fill in the blanK
A .............is a substance which changes the rate of a chemical reaction without undergoing a chemical change.
TRUE \ FALSE
Evaporation of water is a physical change. True or false ?
TRUE \ FALSE
Positively charged electrode is called the anode. True or false ?
Fill in the blank:
The basic conditions necessary for a chemical reaction is _______
State four conditions necessary for a chemical reaction to take place.
Write balanced chemical equations for the reactions represented by word equations in the conditions for chemical reaction.
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.
Give reason for the following:
Colourless concentrated sulphuric acid in a test tube changes to blue on adding a small piece of copper to it.
Explain,giving one example of the following chemical changes:
Reversible reaction
What do you observe when H2S is passed through a lead nitrate solution.
Distinguish by heating the following in dry test tubs.
Ammonium Chloride and iodine.
Select the correct answer for the following options:
The black residue obtained on heating copper carbonate.
Select the correct answer for the following options:
The basic gas obtained when two gases react in presence of a catalyst and the reaction is exothermic.
Complete the table given below.
| Heat on iodine crystals | Colour of vapours evolved |
When lithium metal is placed in hydrochloric acid, _______ gas is evolved.
A bag of cement lying in the open gets wet due to rain during the night. The next day the sun shines brightly. Do you think the changes, which have occurred in the cement, could be reversed?
Water boiling into water vapour is an example of chemical change.
On heating calcium carbonate gets converted into calcium oxide and carbon dioxide.
(a) Is this a physical or a chemical change?
(b) Can you prepare one acidic and one basic solution by using the products formed in the above process? If so, write the chemical equation involved.
When milk is mixed with coffee decoction, the colour of milk and decoction changes due to ______.
