Arrange the following elements in decreasing order of their radii:
(A) La
(B) Pr
(C) Gd
(D) Yb
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The quantity of charge required to obtain one mole of aluminum from \(\text{Al}_2\text{O}_3\) is :

Answer the questions on the basis of passage given below :
As aldehydes ketones possess the carbonyl functional group, they show similar reactions. They exhibit nucleophilic addition reactions, reduction, oxidations, reactions due to alpha-Hydrogen atom, and many other reactions, like Cannizzaro reaction to electrophilic substitution reactions (in case of aromatic aldehydes ketones).
These reactions help in the preparation of a number of important compounds, like acetic acid, vinyl acetate, polymers and in perfume and dye industries.
Nucleophilic addition reactions form cyanohydrins, acetals, alcohols and N -substituted derivatives like imine, oxime, semicarbazone, phenylhydrazone Schiff's base. Reactions due to alpha-hydrogen atoms help in formation of aldols and alpha, beta-unsaturated aldehydes ketones.
Which of the following combinations of Grignard's reagent and carbonyl compound can give \(C _6 H _5- C ( OH )\left( CH _3\right)- CH \left( CH _3\right)_2\)
A. \(C _6 H _5 CH _2 MgBr +\left( CH _3\right)_2 CH - CHO\)
B. \(C _6 H _5 MgBr + CH _3- CO - CH \left( CH _3\right)_2\)
C. \(CH _3 MgBr + C _6 H _5- CO - CH \left( CH _3\right)_2\)
D. \(C _6 H _5- CO - CH _3+\left( CH _3\right)_2 CHMgBr\)
E. \(C _6 H _5 CH ( MgBr ) CH _3+\left( CH _3\right)_2 CO\)
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The half life for radioactive decay of C-14 is 5730 years.
A sample of tree had only 80% of C-14 left.
Estimate the age of the tree.
(log 5 = 0.698) (log 4 = 0.602)

Match the complex species given in List-l with the possible isomerism given in List-ll:

List-l Complex species	List-ll Isomerism
(A) \(\left[ Co \left( NH _3\right)_4 Cl _2\right]^{+}\)	(I) optical
(B) cis- \(\left[ Co ( en )_2 Cl _2\right]^{+}\)	(II) ionization
(C) \(\left[ Co \left( NH _3\right)_5\left( NO _2\right)\right] Cl _2\)	(III) coordination
(D) \(\left[ Co \left( NH _3\right)_6\right]\left[ Cr ( CN )_6\right]\)	(IV) geometrical

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Arrange the following compounds in the decreasing order of reactivity towards Sn1 reaction
(A) (Ph)3C-1
(B) (Ph)3C-Br
(C) (Ph)3C-Cl
(D) (Ph)3C-F
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When the electronic configuration of a transition metal element \(X\) in +3 oxidation state is \([ Ar ] 3 d^5\), what is its atomic number?

Mr. Vishnu has an initial investment of Rs. 80,000 in an investment plan. After 3 years, it has grown to Rs. \(1,00,000\), then his rate of return is

\(\text{KMnO}_4\) is a versatile oxidising agent and it can act as a very strong oxidising agent in acidic medium. Identify the correct statement.

Which one of the following is known as cytokine barriers?

In the figure, there are three infinitely long thin sheets having surface charge density \( +3\sigma, -2\sigma \) and \( +\sigma \) respectively. Determine magnitude and direction of the electric field at point A.

Write the IUPAC name for the coordination compound:
[Cr(NH\(_3\))\(_3\)(H\(_2\)\(\mathrm{O}\))\(_3\)]Cl\(_3\)

Choose the correct sequence for the increasing boiling point of the following compounds.
(A) Pentan-1-ol
(B) Butan-2-ol
(C) Ethanol
(D) Propan-1-ol
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