The Magic of Chemical Reactions

01.

True or False: Milk set into curd is a physical change

02.
Name the following: The substances which are input of the chemical reaction

03.
Fill in the Blanks: Representation of chemical reaction with the help of chemical
formulae is a __________

04.
The slow process of decay or destruction of metal due to the effect of air, moisture
and acids on it is known as _____
(a) Corrosion
(b) Reduction
(c) Oxidation
(d) Degradation

05.
Reaction Speed depends on _____
(a) particle size of the reactants,
(b) nature of reagent,
(c) conditions of the reaction,
(d) All of above

06.
Name the following: Reactions where reactants gain Oxygen, or lose Hydrogen

07.
Corrosion can be prevented by _____
(a) Anti-rust solutions
(b) galvanising process
(c) electroplating process
(d) All of the above

08.
True or False: Rust over Iron is a layer of reddish brown colour Iron Oxide, Fe2O3.H2O

09.
Name the following: The resultant (output) substances we get after a chemical reaction

10.
Name the following: Reactions where reactants gain Hydrogen, or lose Oxygen

11.
True or False: Steam is condensed is a Physical Change

12.
Fill in the Blanks: Reactions accompanied by absorption of heat are called ________
reactions

13.
Fill in the Blanks: When oils and fats are oxidized or even allowed to stand for
a long time, they become _______

14.
Name the following: Reactions where Oxidation & Reduction take place simultaneously

15.
Fill in the Blanks: When a more reactive element removes another element, having
less reactivity, from its compound, the reaction is called___________ Reaction

16.
True or False: Chemical Reaction involves breaking and making of bonds between atoms
to produce new substances

17.
Fill in the Blanks: When the number of atoms are same on the LHS & RHS of the chemical
equation, then the equation is said to be a________ equation.

18.
Name the following: The reaction where Acid and Alkali (Base) react to form Salt
and water.

19.
Reactions in which heat is released are called ____
(a) Thermal Reaction
(b) Fission Reaction
(c) Fusion Reaction
(d) Exothermic Reaction

20.
In the reaction:
O3 ? O2 + [O]
[O] is called ___________
(a) Free Oxygen
(b) Oxygen Ion
(c) Nascent Oxygen
(d) Pure Oxygen

21.
The Chemical Formula for POP is __________
(a) CaSO4 . 5H2O
(b) 5CaSO4 . 2H2O
(c) 3CaSO4 . H2O
(d) 2CaSO4 . H2O

22.
Fill in the Blanks: When two or more substances (elements or compounds) combine
to form single product, then the reaction is known as__________ Reaction

23.
The reaction:
C12H22O11 (g) ? 12C + 11 H2O
is a ___________ reaction
(a) Combination
(b) Recombination
(c) Decomposition
(d) Substitution

24.
True or False: The reaction:
2Cu + O2 ? 2CuO
is a Reduction reaction

25.
Plaster of Paris when mixed with water sets into a hard mass called _______
(a) Cement
(b) Gypsum
(c) Limestone
(d) Concrete

26.
The reaction:
CuSO4 + Zn ? ZnSO4 + Cu
is a ___________ reaction
(a) Combination
(b) Displacement
(c) Decomposition
(d) Oxidation

27.
Fill in the Blanks: When a single reactant is broken down to give simple products,
then the reaction is known as_________ Reaction

28.
Fill in the Blanks: When aluminium burns in presence of oxygen, oxide known as _______
is formed

29.
Fill in the Blanks: The pale yellow silver bromide turns ____ when exposed to sunlight

30.
True or False: POP is used in surgical bandages

Answers:

01. False { It is a chemical change }
02. Reactant
03. Chemical Equation
04. (a) Corrosion
05. (d) All of above
06. Oxidation Reaction
07. (d) All of the above
08. True
09. Products
10. Reduction Reaction
11. True
12. Endothermic
13. rancid
14. Redox Reaction
15. Displacement
16. True
17. balanced
18. Neutralization Reaction
19. (d) Exothermic Reaction
20. (c) Nascent Oxygen
21. (d) 2CaSO4 . H2O
22. Combination
23. (c) Decomposition
24. False { It is an Oxidation reaction }
25. (b) Gypsum
26. (b) Displacement
27. Decomposition
28. Alumina
29. grey
30. True