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Correct answer is (D) Fourth carbon atom

Glucose and galactose are both simple structures made of a six-carbon ring. They are almost identical, but galactose differs slightly in the orientation of functional groups around the fourth carbon. Galactose has a higher melting point than glucose as a result of the structural differences.

Correct option is A) have we heard

(I) Reaction of iron with steam: 

When red hot iron interacts with steam, formation of Iron (II, III) oxide and hydrogen takes place. 

3Fe(s) + 4H₂O(g) ⇾Fe₃O₄ (s)+ H₂(g) 

(II) Reaction f calcium with water:

Calcium reacts with cold water to form calcium hydroxide and hydrogen gas. 

Ca(s) + 2H₂O(l) ⇾Ca(OH)₂(aq.) + H₂(g) 

(III) Reaction of potassium with water:

Potassium reacts violently with cold water to produce potassium hydroxide and hydrogen gas. During the process, much heat is generated and hydrogen rapidly burns. 

2K(s) + 2H₂O (l) ⇾2KOH (aq.) +H₂ (g) + heat

1 . Reaction of iron with steam : 

3Fe(s) + 4H₂O(g) → Fe₃O₄(aq)+ 4H₂ (g)                                                    

• Ferrous react with Steam to form iron / ferric oxide and liberates hydrogen gas .

2 . Reaction of clacium with water :

Ca(s) + H₂O(l) → Ca(OH)₂(aq) + H₂(g)

• Calcium reacts with water and produce Calcuim hydroxide and liberates Hydrogen gas .

3 . Reaction of Potassium with water :

2K (s) + 2H₂O(l) → 2KOH(aq) + H₂(g) + Heat

• Potassium reacts with water vigorously and produces Potassium hydroxide and hydrogen gas with large amount of heat .

(a) A – 2,B – 3, C – 4, D – 1

(i) (d) 

(ii) (a) 

(iii) (c) 

(iv) (d) 

(v) (a)

k = \(\frac{0.693}{t^\frac{1}{2}}\) 

k = \(\frac{0.693}{5730}\) years^-1 

t = \(\frac{2.303}{k}\) log \(\frac{Co}{Ct}\) 

let Co = 1 Ct = \(\frac{3}{10}\)  so \(\frac{Co}{Ct}\)= \(\frac{1}{(3/10)}\) = \(\frac{10}{3}\) 

t = \(\frac{2.303}{0.693}\) x 5730 log \(\frac{10}{3}\)

t = 19042 x (1-0.4771)= 9957 years

let the rate law expression be Rate = k [P]^x [Q]^y 

from the table we know that 

Rate 1 = 3.0 x 10^-4 = k (0.10)^x (0.10)^y 

Rate 2 = 9.0 x 10^-4 = k (0.30)^x (0.30)^y 

Rate 3 = 3.0 x 10^-4 = k (0.10)^x (0.30)^y 

\(\frac{Rate\,1}{Rate\,3}\)= (\(\frac{1}{3}\))^y or 1 = (\(\frac{1}{3}\))^y 

So y = 0 

\(\frac{Rate\,2}{Rate\,3}\)= (3)^x or 3 = (3)^x 

So x = 1 

Rate = k [P]

(i) Reaction is a complex reaction. 

Order of reaction is 1.5. 

Molecularity cannot be 1.5, it has no meaning for this reaction. The reaction occurs in steps, so it is a complex reaction. 

(ii) units of k are \(mol^{-\frac{1}{2}}L^{\frac{1}{2}}s^{-1}\)

(i) Square planar 

(ii) Cu²⁺ = 3d⁹ 1 unpaired electron so \(\sqrt 1(3)\) = 1.73BM

M²⁺ = 91.7% , M³⁺ = 8.3 %

CH₃ = C – C – CH₃ But – 1 – yne 

CH₃ – C = C – CH₃ But – 2 – yne 

CH₃ – C – C = CH₃ But – 1 – yne

(i) t_2g⁴ e_g² Paramagentic 

(ii) Dichloridobis(ethane-1,2-diamine)cobalt(III)nitrate

ΔTb = Kb m ΔTb = 101.04 - 100 = 1.04 ^oC 

or m= \(\frac{1.04}{0.52}\) = 2 m 

2 m solution means 2 moles of solute in 1 kg of solvent. 

2 m aq solution of urea means 2 moles of urea in 1kg of water. 

No. of moles of water = \(\frac{1000}{18}\) = 55.5 

Relative lowering of VP = x₂ (where x₂ is mole fraction of solute)

Relative lowering of VP = \(\frac{n_2}{n_1}+n_2\) (n₂ is no. of moles of solute , n₁ is no. of moles of solvent) 

= \(\frac{2}{2}\)+55.5 = \(\frac{2}{57.7}\) = 0.034

1. a

2. d

3. b

4. b

5. b

6. a

The answer is: A

The correct answer is: A

The Answer is : C

The answer is C : V^​​3+,V^{​​​​​​2+},Fe^{​​​​​3+}

Uses of concave mirror : 

(i)  They are used as shaving mirrors.

(ii)  They are used as reflectors in car head-lights, search lights, torches and table lamps. 

(iii)  They are used by doctors to concentrate light on body parts like ears and eyes which are to be examined.

The correct answer is: D

Correct option  (i) Calcium 

Explanation:

The element is likely to be Ca as its oxide have high melting point & It is soluble in water.

Correct option (ii)  HCl

Explanation:

Acid solution reacts with crushed egg shell (CaCO₃) to give a CO₂ gas that turns lime water milky. Since (ii) acid and remaining are salts. 

\(\int\frac{e^{2x}-e^{3x}}{e^x}dx\) = \(\int(e^x-e^{2x})dx\)

 = e^x - \(\frac{e^{2x}}2+c\)

Correct Option (d) N< O < S < Cl

Explanation:

Generally, the electron affinity increases in a period from left to right and decreases in a group from top to bottom.

However, the electron affinity of some elements of II period are less than that of the elements of III period due to small size of atoms of II period. Thus, the order of electron affinity is 

N < O < S < Cl

(C)  3-chloropentane 

(1) (a), (b), (d)only

The presence of particulate matter in polluted air catalyses the oxidation of sulphurdioxide to sulphur trioxide.

2SO₂(g) + O₂(g) → 2S0₃(g)

The reaction can also be promoted by ozone and hydrogen peroxide.

SO₂(g) + O₃(g) → SO₃(g) + O₂(g)

SO₂(g) + H₂O₂(l) → H₂SO₄(aq)

Miller prepared in the laboratory Amino acid.

H₂O(l) ⇌ H₂O(g)      90 gm of H₂O 

ΔH = ΔU +  Δn_gRT  ⇒  5 moles of H₂O

5 × 41000 J =  ΔU + 1 × 8.314 × 373 × 5

ΔU = 189494.39 Joule

Correct answer is (1) lanthanoid metals 

Alloys of lanthanides with Fe are called Misch metal, which consists of a lanthanoid metal (~95%) and iron (~5%) and traces of S, C, Ca and Al.