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Viscosity decrease in the temperature because intermolecular force of attraction decreases.

At higher altitudes, atmospheric condition is less, therefore, air inside balloon exerts less pressure released and it becomes larger and larger.

(i) Surface tension

(ii) Viscosity.

Correct option is: (A) 5.9 L

Molecular weight of \(CO_2\) = 44g/mol

Number of moles\(CO_2\) = \(\frac {11.5}{44}mol\)

= 0.26 mol

Using ideal gas equation

PV = nRT

V = \(\frac {0.26\times 0.082\times 273}{1\, atm}\) 

V = 5.82 L

Correct option is (A) 5.9 L

(a) D = M/V

The volume increases, with the increase of temperature. Therefore, density decrease with the rise of temperature.

(b) Surface tension diminishes with rise in temperature.

(c) Viscosity decreases with the increase of temperature. This is because, increase in temperature increases the average kinetic energy of molecules which multiplies the attractive forces between them.

(d) As the temperature of a liquid is increased, the vapour pressure increases.

Surface tension and viscosity.

Surface tension is responsible for spherical shape of liquid drops.

Liquid drops take up the spherical shape due to the surface tension of water which is caused due to the   tendency  of water molecules to stick together. The spherical shape is having the least possible surface area due to which it can resist any of the external force in the atmosphere.

 Because of surface tension, the molecules tend to minimize the surface area and sphere has minimum surface area.

The inward forces on the surface molecules of a liquid drop tend to cause the surface-to-volume ratio as small as possible. Since surface-to-volume ratio is minimum for the spherical shape so a liquid drop is spherical.

Avogadro number = 6.023 x 10²³

Time taken for distribution the grains

= {6.023 x 10³² x 1s}/{10¹⁰}

= 6.023 x 10¹³ s

= 1.90,956 x 10⁶ years

Moles of gas 12/120 = 0.1

pV = nRT

or, 1 x V = 0.1 x R x (273 + t)    ...(i)

After temperature change p = 1 + 10/100 = 1.1 atm

T = (t + 273 + 10)

= (283 + t) K

∴ 1.1 x V = 0.1 x R x (283 + t)    ...(ii)

Divide (ii) by (i), we have

1.1/1 = {283 + t}/{273 + t}

or, t = -173°C

Substituting the value of t in equation (i)

1 x V = 0.1 x 0.082 x (273 - 173)

or, V = 0.82 L

1 mole of a gas occupies 22400 cc at STP 

KE of 22,400 cc of a gas at STP = KE of 1 mole of a gas at STP 

= 3/2 x RT = 3/2 x 8.314 × 273 = 3404.58 J

KE of 1 cc of a gas = 3404.58/22400 = 0.152 J 

KE of a m³ of a gas = 0.152 × 10⁶ = 152 × 10³ J.

Option : b. 11.2 dm³

Given :

P₁ = Initial pressure = 1 atm 

V₁ = Initial volume = 10.0 cm³ 

P₂ = Final pressure = 3.5 atm 

To find :

V₂ = Final volume 

Formula :

P₁V₁ = P₂V₂ (at constant n and T) 

Calculation : 

According to Boyle’s law,

P₁V₁ = P₂V₂ (at constant n and T) 

∴ V₂ = \(\frac{P_1V_1}{P_2}\)

= \(\frac{1\times 10.0}{3.5}\) 

= 2.857 L

∴ The final volume of the gas in the syringe is 2.857 L.

Liquids have a property, called surface tension, due to which liquids tend to contract (to decrease the surface area). For a given volume of a liquid, since a sphere has the least surface area, hence the liquids tend to form spherical droplets.

In an LPG cylinder, the gas is held as a liquid. There is an equilibrium between the LPG (liquid) and its vapour. The equilibrium vapour pressure does not depend upon the quantity of liquid present there as long as liquid ……….. vapour equilibrium is maintained. 

Therefore, even when half the gas has been used, the pressure excited by ’ the vapour of the gas remains equal to 2.5 atm.

In a LPG cylinder, the gas is held as liquid. There is an equilibrium between the liquid LPG and its vapour. The equilibrium vapour pressure does not depend upon the quantity of liquid present there in as long as liquid = gas equilibrium is maintained.

Therefore, even when half the gas has been used, the pressure exerted by the vapour of gas remains equal to 2.5 atmosphere.

It is due to the fact that at the boiling point of liquid, the heat supplied is used up in breaking off the inter-molecular forces of attraction of the liquid to change it into vapour and not for increasing the temperature of liquid.

Given : 

P₁ = Initial pressure = 1 bar 

V₁ = Initial volume = 2.27 L 

P₂ = Final pressure = 0.3 bar 

To find :

V₂ = Final volume 

Formula : 

P₁V₁ = P₂V₂ (at constant n and T) 

Calculation :

According to Boyle’s law,

P₁V₁ = P₂V₂ (at constant n and T) 

∴ V₂ = \(\frac{P_1V_1}{P_2}\)

= \(\frac{1\times 2.27}{0.3}\) 

= 7.566667 L ≈ 7.567 L

∴ The balloon can stay inflated below the volume of 7.567 L.

All of us are quite familiar with a cooking gas cylinder which contains in its liquefied petroleum gas, often called L.P.G. It is a mixture of different gases such as propane, butane etc. These are so highly compressed that they are in the liquefied form. When the regulator is opened; the liquid escapes from the nozzle of the cylinder into a space where pressure is very less. As a result, there is a sudden increase in volume and the liquid changes to gaseous state. The released gases get mixed with oxygen from air and ignite when burnt.

(i) In summer, the average kinetic energy of the air molecules inside the tyre increases due to high temperature i.e. the molecules move fast due to which the pressure on the walls of the tube increases. If pressure inside is not kept low at the time of inflation, at high temperature, the pressure may become so high that the tyre may burst. 

(ii) The atmospheric pressure decreases on moving to higher altitudes. So, the pressure outside the balloon decreases. To regain equilibrium with the external pressure, the gas inside expands to decrease its pressure. Thus, the size of weather balloon becomes larger and larger as it moves into higher altitudes.

Real gases show ideal gas behaviour only under low pressure and high temperature.

• There is no intermolecular force of attraction within gaseous molecules (at high pressure and low temperature there is appreciable intermolecular force of attraction). 
• The actual volume of the molecule is negligible as compared to total volume of the gas. (At high pressure the gaseous molecule occupy minimum volume, which is not negligible). 

Note: Because of this deviation Van der waal modified the ideal gas pressure and ideal gas volume respectively.

It is due to two assumptions which are made in formulating kinetic molecular theory:

(i) The molecules have negligible volumes, but all real molecules have definite volumes which cannot be neglected, especially at low temperature and high pressure. 

(ii) It was assumed that there is negligible force of attraction between molecules, therefore, molecules moved independently. It is not true, especially at low temperature, and high pressure when the force of attraction between molecules is appreciable.

A. Bacteria

The cell wall of bacteria is made up of "peptidoglycan". The cell walls of the other three are made up of cellulose.

(a) C-Br because Br is more electronegative than H

(b) C-O because O is more electronegative than N

(c) C-O because O is more electronegative than S

The electron release of alkyl group bonded to unsaturated system in which delocalization of electrons takes place through overlap between C – H sigma (σ) orbital and pi (π) bond orbited or vacant p-orbital is known as hyperconjugation.

Because, cell wall of plants is made up of cellulose and pectins.

The relative stability of various classes of carbonium ions may be explained by the number of no-bond resonance structures that can be written for them. Such structures are obtained by shifting the bonding electrons from an adjacent C-H bond to the electron deficient carbon so the positive charge originally on carbon is dispersed to the hydrogen. This manner of electron release by assuming no bond character in the adjacent C-H bond is called Hyperconjugation. Greater the hyperconjugation greater will be the stability of alkenes.

A. (ii) 

B. (iv) 

C. (v) 

D. (i) 

E. (iii)

Keeping beehives in crop fields during flowering period increases pollination efficiency, it improves yield of crops and honey.

Ascariasis is a helminths disease caused by common round worm - Ascaris lumbricales. The main symptoms of ascariasis muscular Internal bleeding, muscular pain, anaemia, blockage of intestinal passage. By intake of  water vegetables,fruits,foods contaminated with the eggs of parasite excreted along with faeces of infected person.

Symptoms of Ascariasis: Internal bleeding, muscular pain, anaemia, blockage of intestinal passage. A healthy person can acquire this infection by intake of water, vegetables/fruits/foods contaminated with eggs of the parasite.

(i) The use of land is determined by physical factor's such as to topography, climate, soil types, etc.

(ii) It is also determined by human factors such as population density, technological capability, cultural and traditions, etc.

(i) Renewable resources: Resources which can be renewed or reproduced by mechanical. Physical or chemical processes are known as renewable or replenishable resources, e.g., solar and wind energy, water, forests and wildlife, etc.

(ii) Non- renewable resources: These occurs over very long geological times. Minerals and fossil fuels are examples of such resources. These resources take millions of years in their formation. Some of the resources like metals are recyclable and some of them such as fossil fuels cannot be recycled and get exhausted with their use.

(i) Renewable resources: Resources which can be renewed or reproduced by mechanical. Physical or chemical processes are known as renewable or replenishable resources, e.g., solar and wind energy, water, forests and wildlife, etc.

(ii) Non- renewable resources: These occurs over very long geological times. Minerals and fossil fuels are examples of such resources. These resources take millions of years in their formation. Some of the resources like metals are recyclable and some of them such as fossil fuels cannot be recycled and get exhausted with their use.

Resources are vital for human survival and it was believed that resources are free gift of nature. The indiscriminate use of resources led to the following problems:

(i) To satisfy the greed of few individuals, depletion of resources has continued.

(ii) Due to the accumulation of resources in few hands, the society gets divided into two segments, i.e'., rich and poor.

(iii) Indiscriminate use of resources has led to ecological crises, e.g., ozone layer depletion, land degradation, global warming and environmental pollution.

Yes, indiscriminate use of resources led to numerous problems. The problems faced by indiscriminate use of resources are:

(i) Exploitation of resources by greedy and powerful people lead to a massive depletion of resource and deprives the weak and future generation.

(ii) Accumulation of resources in the hands of few individuals dividing the society into haves and have nots or rich and poor.

(iii) Over exploitation of land resources, forest resources, etc led to imbalance ecological set up and creates global ecological crisis.

Red soil

1. Red soil develops on crystalline igneous rocks in areas of low rainfall.

2. Red soil is found in parts of Odisha and Chhattisgarh, southern parts of the middle of Ganga plain and along the piedmont zone of the Western ghats.

3. Red soil develops a reddish colour due to diffusion of iron in crystalline and metamorphic rocks.

Laterite soil

1. Laterite soil develops in areas with high temperature and heavy rainfall.

2. Laterite soil is mainly found in Karnataka, Kerala and the hilly areas of Odisha and Assam.

3. In laterite soil, humus content is very low.

(i) Classification for resources on the basis of ownership:

(a) Individual resources

(b) Community owned resources

(c) National resources

(d) International resources

(a) Individual resources: Resources which are privately owned against the payment of revenue by individuals. e.g., ponds, pasture lands etc.

(b) Community owned resources: Resources which are accessible to all the members of a community, e.g., picnic spots.

(c) National resources: AII the resources (minerals, water resources, forests, wildlife, land) which are present in the political boundaries and oceanic area of a nation up to 12 nautical miles in the ocean from the coast, termed as terrestrial water and resources therein belong to the nation.

(d) International resources: There are international institutions which regulate some resources. The oceanic resources beyond 200 nautical miles of the Exclusive Economic Zone belong to open ocean and no individual country can utilise these without the concurrence of international institutions.

Alluvial soil is found in the river deltas of the eastern coast. Alluvial soil is rich in potash, phosphoric acid and lime. It has a high water retention capacity and it is highly fertile soil.

Methods of soil conservation:

(i) Ploughing along the contour lines can decrease the speed o[ water flow down the slopes.

(ii) Step or terrace cultivation on slopes restricts erosion. Western and Central Himalayas have well-developed terrace farming.

(iii) Strip cropping: Here large fields can be divided into strips. Strips of grass are left to grow between the crops. This breaks up the force of the wind.

(iv) Shelterbelt plantation: Tree is planted in rows. These shelterbelts have led to the stabilisation of sand dunes and in stabilising the desert in western India.

Karnataka, Kerala, Tamil Nadu, Madhya Pradesh, and hilly areas of Odisha and Assam

Alluvial soil is found in the entire northern plain. It is the most widely spread soil of India. Main features of alluvial soil:

(i) It is formed by the deposition of materials brought down by the Himalayan rivers.

(ii) It is highly fertile.

(iii) It consists of various proportions of sand, silt and clay.

(iv) It is rich in potash, phosphoric acid and lime but deficient in organic matter.

Maharashtra, Saurashtra, Malwa, Madhya Pradesh and Chhattisgarh

Correct option is  A) Nellore