Question

Plz solve.................xd​

Answer 1

Answer:

1. (Please refer to attached photo)

2.

• Fertilizers are chemical in nature and these are  manufactured in factories.
• Manure is an inorganic substance that is obtained from decomposition of vegetable and animal wastes.

• Microbes are not needed for fertilizers formation.
• Microbes are needed to form manure since they degrade the organic substances.

• Fertilizers are easy to transport ,store and apply to crops.
• Manures is difficult to transport ,store and apply manure to crops

• Fertilizers do not restore soil texture.
• Manure restore soil texture.

• Fertilizers do not help in retention of water.
• Manure help in the retention of water.

3.

Petroleum formation occurs by various hydrocarbons combining with certain minerals such as sulphur under extreme pressure. Modern day scientists have proven that most if not all petroleum fields were created by the remains of small animal and plant life being compressed on the sea bed by billions of tons of silt and sand several million years ago.

When small sea plants and animals die they will sink, they will then lie on the sea bed where they will decompose and mix with sand and silt. During the decomposition process tiny bacteria will clean the remains of certain chemicals such as phosphorus, nitrogen and oxygen.

This leaves the remains consisting of mainly carbon and hydrogen.

As the depth of the sediment build up increases the weight of the sand and silt pressing down on the mass will compress it into a layer which is much thinner than the original.

Finally, when the depth of the buried decomposing layer reaches somewhere around 10,000 feet the natural heat of the earth and the intense pressure will combine to act upon the mass. The end result, over time, is the formation of petroleum.

With petroleum formation the actual temperature applied to the original organic mass is critical in determining the overall properties of the resulting petroleum. Typically lower temperatures during petroleum formation will result in thicker, darker raw petroleum deposits, the most solid of which being a bitumen substance.

If the heat applied during the formation of petroleum process fluctuates too much then gas will be produced, often separating from the petroleum, sometimes remaining mixed with the raw oil. If temperatures are too high, in the somewhere over 450 degrees Fahrenheit then the original biomass will be destroyed and no gas or petroleum is formed.

As the mud and silt above the deposit become heavier and the forces placed upon the silt and mud begin to change the bottom layers of the compressing layer above the petroleum then it will turn into shale.

As we can see, the formation of naturally occurring raw petroleum takes millions of years, certainly far longer than can be deemed renewable, yet mankind has managed to almost complete deplete the world supply in little more than a century.

4. i) Because zinc is more reactive than copper. More reactive metal displaces less reactive metal from its salt solution. Zinc has displaced copper, but copper cannot do so

ii) Aluminium is the least reactive metals so it does not react with food items and does not alter the taste. Moreover, being a metal ; aluminium is highly malleable and can be made into very thin foils which are perfect for wrapping.

iii) Because it is a bad conductor of heat and does not get heated up while cooking.

Answer 2

Answer:

ii) Manure is decomposed organic matters. Fertilizer is man made and contains harmful chemicals.

Manure contains nitrogen, one of the most beneficial substances for soil. Fertilizer may or may not contain nitrogen.

Manure can be used as fertilizer. A fertilizer may not act as a manure.

iii) Petroleum is formed by dead organic matters which turned into liquid over millions of years.

iv) a. Copper is a less reactive metal and cannot displace the more reactive zinc.

b. Aluminum foil is used to wrap food because it protects the food from light, bacteria, etc.

c. Thermosetting plastics are bad conductors of heat and hence used to cover handles of saucepans to prevent our hands from getting burnt.

v) Sex hormones like oestrogen or testosterone are steroid hormones naturally produced by the body. These hormones help the growth of the reproductive organs and reproduction.

vi) Asexual reproduction means the reproduction without the combination of two different organisms.

Examples asexual reproduction in animals. By fragmentation, when parts of the body break off from the parent body.

Budding, when a new adult is formed on the parent body.

vii) By planting more trees, by preventing others from cutting down trees, by spreading awareness on environmental conservation and preservation. By reducing all forms of pollution of land, air and water.

viii) Weeds are the fast growing but unwanted plants which prevent healthy growth of garden plantation and field crops.

Weeds can be controlled by:

(1) Mechanical method which involves the use of farm equipment.

(2) Biological method which involves the use of natural enemies of weed.

(Length and details of answers according to the marks of the question paper)