Question

Holiday's Homework (2020)
Class VIII
Subject : Science

1. Answer the following questions:-
i) Sowing with seed drill is better. Give reasons.
ii) It is recommended to use manure instead of chemical fertilisers. Why?
iii) What would be the consequences of not fumigating and drying of the granaries?
iv) Explain the sprinkler system of irrigation.
v) Of what use is crop rotation? Explain giving at least two examples.
vi) Who are called the friends of farmer and why?
vii) Explain mixed cropping with examples.
viii) Aluminium is a metal that is used for various purposes. Write down the properties because of which it is used to make :
a) Saucepans
b) Door frames
c) Cooking foil
d) Power cables
ix) A student had three metals X,Y and Z. Metal X reacts with diluted hydrochloric acid but not with water. Metal Y reacts with both water and diluted hydrochloric acid. Metal Z reacts with either water or hydrochloric acid.
a) Determine the reactivity of the metals.
b) Identify metals X,Y and Z
x) Differentiate between oxides of metals and oxides of non metals giving examples.
xi) Why is phosphorus stored in water?
xii) Why is it advised not to store sour food items in metal containers?
xiii) Manu placed a piece of copper in zinc sulphate solution. He did not observe any change occuring. Can you explain why?
xiv) Name the following :
a) A liquid metal
b) A gaseous non metal
c) A liquid non metal
xv) Differentiate between petroleum and petrol?
xvi) Give three ways in which the formation of coal and petroleum are similar.
xvii) What does PCRA stands for?
xviii) Where was first oil well drilled in world and in India?
xix) What is fractionating column?
xx) Name any four places in our country where reserves of natural gas are found.


2. Project

Prepare a brief research report on COVID-19 Virus Outbreak using following points:
i) Casual organism
ii) Origin
iii) Mode of transmission
iv) Symptoms
v) Treatment
vi) Preventive measures
Explain what changes will come in life even after getting rid of this disease.​

Answer 1

Answer:

why very long question please ask one question at a time