Advertisements
Advertisements
प्रश्न
Fill in the blank.
Melting of ice is a _______ change.
Advertisements
उत्तर
Melting of ice is a physical change.
APPEARS IN
संबंधित प्रश्न
State whether the following statement is true or false. In case a statement is false, write the corrected statement.
Iron and rust are the same substances.
FILL IN THE BLANK
Positively charged ions are called ........
Fill in the blank
A new substance is formed in a _______ change.
Write true or false :
When iron and sulphur are heated together a grey mass is formed which is attracted by a magnet .
State the conditions necessary for a chemical change or reaction.
Define the following term:
Precipitate
Give reason for the following:
Blue solution of copper sulphate changes to green when a piece of iron is added to this solution.
Explain,giving one example of the following chemical changes:
Reversible reaction
State the type of reactions for the following represent and balance the ones that are not balanced.
NaOH + HCl → NaCl + H2O
Name: Two nitrates that do not produce nitrogen dioxide on heating.
State the original colour of the following substance and colour of residue obtained after heating.
Ammonium dichromate
Distinguish by heating the following in dry test tubs.
Zinc nitrate and copper nitrate.
Give balanced equation for the following conversion affected by heat alone on the substance:
Copper carbonate to copper oxide
Give a balanced equation for a reaction involving the evolution of gas on the addition of dilute acid to calcium carbonate.
Complete the statement by filling in the blank with the correct word:
The reddish-brown precipitate obtained during a double decomposition precipitation reaction between an iron salt and alkali is __________.
A thick coating of a paste of Plaster of Paris (POP) is applied over the bandage on a fractured bone. It becomes hard on drying to keep the fractured bone immobilised. Can the change in POP be reversed?
Chemists identify gypsum as a natural indicator.
Iron benches kept in lawns and gardens get____________. It is a _________ change because a new _________ is formed.
Write a note on the catalyst.
We are advised to not to play with fireworks. Give reason.
