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Answer is (1) – 333, – 349, – 325 and – 296

Order of electron gain enthalpy (magnitude) is

Cl > F > Br > I

Answer is (1)

Electron gain enthalpy of Cl > F > Br > I

At Cathode —

Cu⁺²(aq) + 2e^- → Cu(s) (Reduction)

At Anode —

\(2\bar OH+\overset{-}{\longrightarrow}\) H₂O + 1/2 O₂ + 2e^- (Oxidation)

Due to the small size, the ionisation enthalpies of Be and Mg are much higher than those of other alkaline earth metals. This means that the valence electrons in beryllium and magnesium are more tightly held by the nucleus. Therefore, they need large amount of energy for excitation of electrons to higher energy levels. Since such a large amount of energy is not available in bunsen flame, therefore, these metals do not impart any colour to the flame.

Alkali and alkaline earth metals are themselves very strong reducing agents and reducing agents stronger than them are not easily available. Therefore, these metals cannot be obtained by chemical reduction methods.

(a) False. Alkali metals possess only +1 oxidation state. 

(b) True 

(c) True 

(d) False. Washing soda is used to remove the permanent hardness.

1. All the alkali metal halides are soluble in water except LiF. They have high negative enthalpies of formation. 

The melting and boiling points always follow the trend:

fluoride > chloride > bromide > iodide. 

2. Alkali metal halides are prepared by the reaction of the appropriate oxide, hydroxide or carbonate with aqueous hydrohalic acid.

(a) Calcium hydroxide 

(b) It is disinfectant hence it is used in white wash. 

(c) Calcium hydroxide is obtained by adding water to quick lime. This process is called slaking of lime. 

(d) Calcium hydroxide reacts with dry chlorine to form calcium hypochlorite, a constituent of bleaching powder. 

2Ca(OH)₂ + 2Cl₂ → CaCl₂ + CaOCl₂ + 2H₂O

(d) Cs. 

As the atomic size of the metal increases, the strength of metallic bonding decreases and hence its melting point decreases. Since the size of Cs is the largest, therefore its melting point is the lowest.

1. Gypsum

2. 393 K 

3. Plaster of Paris (CaSO₄ . ½H₂O) or (CaSO₄) .H₂O

1. The solution turns into blue. 

2. The blue colour of the solution is due to the presence of solvated electrons. 

3. On standing, the solution slowly liberates hydrogen resulting in the formation of amide. 

4. When the concentration of the solution increases the colour turns bronze and the solution becomes diamagnetic.

1. Castner-Kellner method 

2. The Castner-Kellner cell consists of a large tank. The bottom of the tank is filled with mercury. The tank is made into 3 compartments by 2 partitions. The outer compartments are filled with NaCl solution and the middle compartment is filled with a very dilute solution of NaOH. The mercury layer of the bottom of cell in the outer compartments acts as cathode and the mercury in the middle compartments acts as anode. As a result of electrolysis Na and Cl₂ are produced in the outer compartments. Na gets coated with mercury, and sodium amalgam is produced in the outer compartments. Due to the action of eccentric wheels at the bottom of the tank, the tank can be tilted. As a result of this Na is carried into the middle compartment and is then allowed to react with water in the middle compartment. As a result of this reaction NaOH is produced. When the concentration of NaOH in the middle compartment is raised to 40%, it is taken out from the tank. On cooling, crystals of NaOH separate out.

3. NaCl → Na⁺ + Cl^- 

At cathode: Na⁺ + e^- → Na 

Na + Hg → Na/Hg (Sodium amalgam) 

At anode: Cl^- → Cl + e^- 

Cl + Cl → Cl₂ (g)

A. False It is carried as carbamino hemoglobin; carboxy hemoglobin is the combination of hemoglobin with carbon monoxide. 

B. False It decreases as the oxygen dissociation curve is shifted to the right. 

C. False HCO₃^-  ions increase more; H⁺ ions are largely buffered by hemoglobin. 

D. False Breathing 20 per cent CO₂ causes respiratory depression; stimulation of respiration by CO₂ is maximal when breathed at concentrations of around 5 per cent. 

E. True CO₂ content in arterial blood is about 500 ml/l; O₂ content is about 200 ml/l.

Mg₂C₃ on hydrolysis gives Propyne.

limestone & clay

(b) CaSO₄, 2H₂O

Gypsum (CaSO₄, 2H₂O) is usually added to prevent early hardening and increase the settling time

Correct option is (B) CaSO₄.2H₂O

Gypsum (CaSO₄.2H₂O) is used to enhance setting time in portland cement.

Correct option is D. (i)- continuous synthesis , (ii)- discontinuous synthesis (iii) 3’ end (iv) 5’end

Correct option is C: (i) Promotor Site, (ii) Sigma factor (iii) RNA polymerase

b. Both assertion and reason are true, but reason is not the correct explanation of assertion.

Bacteria  is active in treatment of sewage.

Correct option is D. Hydroxyl

Correct option is C. secretes oxytocin

Deficiency of Adenosine deaminase can be overcomed by Gene therapy.

Correct option is A. It verifies that DNA is the carrier of genetic information.

A person suffering from colourblindness can not differentaite between  Red and green colour.

1. Position the client according to the area being waxed, taking into account the mobility and comfort of the client. 

2. Protect the client’s clothes with towels and disposable paper. 

3. When waxing the eye brows, apply eye pads to protect the eyes and petroleum jelly to control the amount of hair being removed. 

4. Remove all Jewellery in the areas to be waxed.

Guidelines for conducting a skin sensitivity test before waxing. 

1. Sensitivity test should be performed on the forearm as is free from hair, clean and dry. 

2. Perform the test 24 hours before the treatment. 

3. Check the wax for operating temperature by applying the wax on to the forearm. 

4. Observe for any reactions on the skin after removing the wax.

It is advised to give microdermabrasion or ultrasonic exfoliation treatment on sensitive and thicker skin to remove dead skin cells to even out the skin tone. This helps to stimulate circulation of the blood and make the skin smooth. 

Procedure: 

1. Apply water solution on the skin to loosen surface dead skin cells. 

2.Use an ultrasonically activated spatula, lift dead cells of the skin and infuse water solution deep into the skin and hydrate new cells. 

Contra Indication: 

1. Skin diseases 

2. Acute infectious diseases 

3. Pregnancy

The poem describes nature as seen in the month of march, so it as called ‘March’. It is spring time.

The minerals that are required to keep our bones healthy are calcium and vitamin D. We need sufficient calcium to keep our bones healthy and vitamin D helps to absorb the calcium.

Self-incompatibility is a spread mechanism in flowering plants that prevents in breeding and promotes out crossing and response in genetically controlled. In favor cross pollination the in to different male and female gametes.

(a) Marsh gas

Correct option is (D) O^2--and Mg²⁺ 

Isoelectronix species have same no. of electrons Al⁺³, O^2-, Mg⁺² all have 10 electrons.

Answer: (3) K₃[Fe(CN)₆] < K₂CrO₄ < KNO₃ = KBr = AlCl₃ 

According to hardy-schultz rule,

Coagulation value or flocculation value ∝ 1/Coagulation power

Given:

number 1240

Formula used:

Odd factors of  pa × qb = (a +1)(b + 1),

Where p and q should be odd prime numbers

Calculation:

Factor of 1240 = 23 × 51 × (31)1

⇒ Odd number are 51 × (31)1

⇒ Odd factors of pa × qb

⇒ (a +1)(b + 1)

⇒ (1 + 1)(1 + 1) = 4

∴ 1240 has 4 odd factors

Here is Reaction with Balance

10FeC₂O₄ + 6KMnO₄ + 24H₂SO₄ ----> 3K₂SO₄+ 6MnSO₄ +  5Fe₂(SO₄)₃ + 24H₂O + 20CO₂

So we see that

 6 moles of KMnO₄ is required to oxidize 10 moles of  FeC₂O₄ 

Then, 1 mole of FeC₂O₄ would be oxidized by = ?

6/10=0.6

(i) ³⁵₁₇Cl

(ii) ²³³₉₂U

(iii) ⁴₉Be

The metal which gives photoelectrons most easily is Cesium.

(c) The electrons in them have fixed energy

Mass of organic compound = m = 0.24 g 

Mass of carbon dioxide formed = 0.62 g 

Mass of water formed = 0.11 g

Percentage of carbon = 12/4 x 0.62/0.24 x 100 = 70.45

Percentage of hydrogen = 2/4 x 0.11/0.24 x 100 = 5.09

Percentage of oxygen = [100 – (70.5 + 5.0)] = 24.46

Correct option: (a) 1.4 x 10^–2

Explanation: 

More is K_a, lesser is pK_a(pK_a = – log K_a), more is acidic strength.