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Breaking strength of glass is 50 × 10⁶ Nm^-2

Using Stress = \(\frac{F}{A}\),

We get F = stress × A

= (50 × 10⁶) × π × \((\frac{10^{-2}}{2})N\)

Largest mass = \(\frac{(50\times 10^6)(\frac{π\times 10^{-4}}{4})}{10}kg\)

= 392.7 kg

• In the manufacture of sodium hydroxide, hydrogen gas and chlorine gas (X) are formed as by–products. 
• When chlorine gas (X) reacts with lime water, it forms calcium oxychloride (bleaching powder) Y. 
• The reactions are :

2NaCl (aq) + 2H2O(l) → 2NaOH (aq) + Cl₂(g) + H₂(g) 

X→ Cl₂ (Chlorine gas) 

Ca (OH)₂ (s) + Cl₂ (g) → CaOCl₂ (s) + H₂O

Y — Calcium oxychloride (bleaching powder)

Beam is ordinarily a bar supported at its ends.

It is used in the construction of a roof or a bridge.

δ = \(\frac{ωl^3}{4Y6d^3}\)

1. (iii) Methanoic acid

2. (ii) Dock

3. (i) TRUE

4. (i) YES

5. (ii) Basic

1. (ii) 2

2. (i) CaSO₄. \(\frac12\)H₂O

3. (ii)  CaSO₄. 2H₂O

4. (ii) 373

5. (ii) FALSE

Chemically chloride of lime is known as calcium oxychloride.

The commonly used solvents are water, ethyl alcohol, methyl alcohol, acetone, ether or their combinations.

Fractional crystallization is a process wherein two or more soluble substances having widely different solubilities in the same solvent at same temperature are separated by crystallization.

Morphine, cocaine and heroin.

Correct option is  D) Moeller

Option : (A) Water

Ultraviolet rays and X-rays.

a. Solvent extraction : 

Solvent extraction is a method used to separate an organic compound present in an aqueous solution, by shaking it with a suitable organic solvent in which the compound is more soluble than water.

b. Distillation : 

The process in which liquid is converted into its vapour phase at its boiling point and the vapour is then condensed back to liquid on cooling is known as distillation.

The solvent to be used for crystallization should have following properties :

• The compound to be crystallized should be least or sparingly soluble in the solvent at room temperature but highly soluble at high temperature.
• Solvent should not react chemically with the compound to be purified.
• Solvent should be volatile so that it can be removed easily.

Depending on the nature of the stationary phase i.e., whether it is a solid or a liquid, chromatography is classified into adsorption chromatography and partition chromatography.

i. Adsorption chromatography : 

This technique is based on the principle of differential adsorption. Different solutes are adsorbed on an adsorbent to different extent.

Adsorption chromatography is further classified into two types :

1. Column chromatography 

2. Thin-layer chromatography

ii. Partition chromatography : 

This technique is based on continuous differential partitioning of components of a mixture between stationary and mobile phases. 

For example,

Paper chromatography.

i. Preparation of a saturated solution :

• A saturated solution of the crude solid is prepared by boiling it in a small but sufficient quantity of a suitable solvent.
• On doing so the main solute forms an almost saturated solution, but the solution is not saturated with respect to the soluble impurities, as they are in small proportion.

ii. Hot filtration : 

The hot saturated solution is quickly filtered to remove undissolved impurities as residue. Filtration under suction can be employed for rapid filtration.

iii. Cooling of the filtrate :

• The hot filtrate is allowed to cool. 
• On cooling, the filtrate becomes supersaturated with respect to the main dissolved solute because solubility of a substance decreases with lowering of temperature. 
• The excess quantity of the dissolved solute comes out of the solution in the form of crystals.
• The dissolved impurities, however, do not supersaturate the solution, as their quantity is small.
• These continue to stay in the solution in dissolved state even on cooling. Therefore, the separated crystals are free from soluble impurities.

iv. Filtration :

• The crystals obtained on cooling are further purified by filtration to remove insoluble impurities.
• The filtrate obtained is called as mother liquor.
• The crystals obtained after filtration are free from soluble as well as insoluble impurities.

Steps involved in the process of crystallization :

• Preparation of a saturated solution 
• Hot filtration 
• Cooling of the filtrate 
• Filtration 

UV rays and 5-bromouracil. 

The property of tumour cells by which they move in the body fluid to different sites away from their site of origin is called malignancy.

B) excited state

Yes. The weight of a object will be decreased because the gravitational force is weak i.e., the value of acceleration due to gravity becomes less on the moon.

The mass of a body on the moon is 60 kg. There will be no change in mass because it is still made up of same amount of matter.

Harm caused by cancerous cells: 

i. The cancerous cells may increase in numbers and size to cease normal function of the cells. 

ii. Cancerous cells compete with normal cells of the body for nutrients and in turn kill them.

A. Reverse transcription. 

B. Viral DNA incorporates into host genome. 

C. New viral RNA produced by infected cell. 

D. New viruses can infect other cells.

ELISA stands for enzyme linked immuno-sorbent assay. It is a widely used diagnostic test for AIDS.

Correct option is  C) Aufbau

B) ground state

Correct option is a. angular and non–zero

Ratio of masses m_{1 :} m₂ = 1 : 3

Ratio of applied forces F_{1 :} F₂ = 4 : 9

Accelerations a = \(\frac{F}{m}\)

Acceleration of first body ,

a₁ = \(\frac{F_1}{m_1}\)

= \(\frac{4}{1}\) = 4

Acceleration of second body,

a_{2 =} \(\frac{F_2}{m_1}\)

Ratio of their accelerations is 4 : 3

Given, 

m₁ = 15 kg, m₂ = 10 kg, F = 500 N 

Tension acting in the string T = \(\frac{m_2}{m_1 + m_2}\) F 

T = \(\frac{10}{25}\) x 500 = 200 N

A) Energy is fixed

Correct option is b. zero

Correct Answer is: (b) Planaria

(d) Sporogony

The detachment of gravid proglottids either singly or in groups from the body of tapeworm is called apolysis.

Schizogony: 

1. In schizogony, the multiple fission occurs in the schizont. 

2. It results in the formation of merozoites.

Sporogony: 

1. In sporogony, the multiple fission occurs in the oocyte. 

2. It results in the formation of sporozoites.

Correct Answer is: (b) pig

Interferons protect non-infected cells from further viral infections, by creating cytokine barriers.

The natural proteins (glycoproteins) produced by the cells of immune system in response to viral infection which protect non-infected cells from further infection are called interferons. Interferons inhibit the viral replication within host cells, activate natural killer cells and macrophages, increase antigen presentation to lymphocytes and induce resistance of host cells to viral infection. When the antigen is presented to specific T-cells and B-cells, these cells multiply and remove the foreign substance.

Under unfavorable conditions, When the products of multiple fission become individually surrounded by resistant coats, the cyst walls before their release from the parent, the process is known as sporulation and the encysted products are termed spores. 

E.g- Amoeba

Statement:

The brightly coloured female flowers have long stalk to reach the surface.

• If spotting of a mixture is done at the level of mobile phase, then solvent will come in contact with the sample spot.
• Sample spot will dissolve in the mobile phase and its components will move all over the plate resulting in no distinct separation.

Hence,

Spotting of mixture should be done above the level of mobile phase.

When several forces act simultaneously on the same body, then the combined effect of the multiple forces can be represented by a single force, which is termed as ‘resultant force’.

1. Produces or tries to produce the motion of a static body. 

2. Stops or tries to stop a moving body. 

3. Changes or tries to change the direction of motion of a moving body.

(B) An isotone of ⁷⁶₃₂Ge is  ⁷⁷₃₃As.

a. Stationary phase : 

Stationary phase is a solid or a liquid supported on a solid which remains fixed in a place and on which different solutes are adsorbed to a different extent.

b. Saturated solution : 

A saturated solution is a solution which cannot dissolve additional quantity of a solute.

B) Sommerfeld

C) It explains fine spectrum of hydrogen atom

The distribution of electrons in an orbit is obtained by 2n², where ‘n’ is number of orbit.

Therefore,

Number of electrons in K-shell i.e. in 1st orbit.

Here n = 1

Therefore,

2n² = 2 x 1² = 2

Thus, maximum number of electrons in K-shell i.e. 1st shell = 2

Number of electrons in L-shell, i.e. in 2nd orbit

Here n = 2, therefore,

2n² = 2 x 2² = 8

Thus, maximum number of electrons in L-shell = 8

Number of electrons in M-shell, i.e. in 3rd orbit

Here n = 3, therefore,

2n² = 2 x 3² = 18

Thus, maximum number of electrons in M-shell = 18

Number of electrons in N-shell, i.e. in 4th shell

Here n = 4, therefore,

2n² = 2 x 4² = 32

Thus, maximum number of electrons in N-shell = 32

In similar way maximum number of electrons in any shell can be calculated.