Advertisements
Advertisements
प्रश्न
Give reason for the following:
Even though rusting is an exothermic reaction, the heat evolved when an iron nail rusts is unnoticeable.
Advertisements
उत्तर
Rusting of iron – the reaction is slow and the heat evolved is very less, hence unnoticeable.
APPEARS IN
संबंधित प्रश्न
How do the following help in bringing about a chemical change?
light.
Complete and balance the following chemical equations
Na + H2 O →
Complete and balance the following chemical equations
NaCI + `AgNO_3` `→`
Give reason .
A person suffering from acidity is advised to take an antacid.
Explain the type of reactions on the basis of the direction of reaction.
How is a strong electrolyte different from a weak electrolyte?
Fill in the blank:
The substances formed as a result of a chemical reaction are called _______
Write true or false :
When potassium iodide solution is added to lead acetate solution a red precipitate is formed.
Complete the statement by filling the gap using an 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)
An ______ is drawn in between the reactants and products while writing the equation for a chemical reaction.
Choose the correct option from the bracket and explain the statement giving reason.
(Oxidation, displacement, electrolysis, reduction, zinc, copper, double displacement, decomposition)
The conversion of ferrous sulphate to ferric sulphate is ______ reaction.
Name the gases which turn moist red litmus blue.
State the original colour of the following substance and colour of residue obtained after heating.
Zinc carbonate
Give balanced equation for the following conversion affected by heat alone on the substance:
Hydrated copper sulphate to sulphur dioxide
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 __________.
________ is a chemical substance which alters the speed of a chemical reaction.
Melting of wax is a change where a solid changes to liquid state. Give one more such change which you observe in your surroundings
Iron benches kept in lawns and gardens get____________. It is a _________ change because a new _________ is formed.
Rusting of iron is ______.
Is the conversion of milk into ice cream a chemical change?
Write a note on the following:
Fermentation
