Question

I which among the following is not a physical change?
a) Melting of ice
b) Breaking chalk into pieces
c) Rusting of iron
d) Dissolving sugar in water
2 Chemical reactions are accompanied by
a) formation of a precipitate
b) evolution of gas
c) change in colour
d) all the above
3. Reduction reaction involves
a) reducing the compound into element b) addition of hydrogen
c) removal of hydrogen
d) none of the above
4. A chemical reaction in which more reactive element is displaced by least reactive one from the
compound is called
a) combination reaction
b) neutralisation reaction
c) displacement reaction
d) precipitation reaction
5. When an acid reacts with base forming salt and water, the reaction is called
a) decomposition reaction
b) precipitation reaction
C) neutralisation reaction
d) reduction reaction​

Answer 1

Answer:

1.a) Rusting of Iron

2.d) all the above

3.b) addition of hydrogen

4.c) displacement reaction

5.c) neutralization reaction