Forum

Chemical Reactions and Equations

Which of the following are exothermic processes?
(i) Reaction of water with quick lime
(ii) Dilution of an acid
(iii) Evaporation of water
(iv) Sublimation of camphor (crystals)
(a) (i) and (ii) (b) (ii) and (iii) (c) (i) and (iv) (d) (iii) and (iv)

06/11/2024

Science

10th

Chemical Reactions and Equations

Which of the following statements about the given reaction are correct?
3Fe(s) + 4H2O(g) → Fe3O4(s) + 4H2(g)
(i) Iron metal is getting oxidised
(ii) Water is getting reduced
(iii) Water is acting as reducing agent
(iv) Water is acting as oxidising agent
(a) (i), (ii) and (iii) (b) (iii) and (iv) (c) (i), (ii) and (iv) (d) (ii) and (iv)

06/11/2024

Science

10th

Chemical Reactions and Equations

The following reaction is an example of a
4NH3(g) + 5O2(g) → 4NO(g) + 6H2O(g)
(i) displacement reaction
(ii) combination reaction
(iii) redox reaction
(iv) neutralisation reaction
(a) (i) and (iv) (b) (ii) and (iii) (c) (i) and (iii) (d) (iii) and (iv)

06/11/2024

Science

10th

Chemical Reactions and Equations

Which of the following is not a physical change?
(a) Boiling of water to give water vapour
(b) Melting of ice to give water
(c) Dissolution of salt in water
(d) Combustion of Liquefied Petroleum Gas (LPG)

06/11/2024

Science

10th

Human Resources

What are population pyramids? How do they help in understanding
about the population of a country?

06/11/2024

SST

8th

Human Resources

What is meant by population composition?

06/11/2024

SST

8th

Human Resources

Discuss the role of any two factors influencing population change.

06/11/2024

SST

8th

Human Resources

The world population has grown very rapidly. Why?

06/11/2024

SST

8th

Statistics & Probability

A total of 25 patients admitted to a hospital are tested for levels of blood sugar, (mg/dl) and the results obtained were as follows :
87 71 83 67 85
77 69 76 65 85
85 54 70 68 80
73 78 68 85 73
81 78 81 77 75
Find mean, median and mode (mg/dl) of the above data.

06/11/2024

Mathematics

9th

Human Resources

What are the causes for the uneven distribution of population in
the world?

06/11/2024

SST

8th