The chemical formula of Magnetite is :

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The carbonyl group of aldehydes and ketones is highly polar. The positively charged carbon is readily attacked by electron-rich nucleophile and the negatively charged oxygen atom is attacked by an electro-deficient electrophile. Aldehydes and ketones undergo nucleophilic addition reactions in the presence of acid or a base. The mechanism involves attack of a nucleophile on the electron deficient carbonyl carbon to form a tetrahedral intermediate. A new bond is formed between the carbon and oxygen. Protonation of the anion furnished by the reaction medium yields a neutral addition product. The addition product is same whether the reaction is catalyzed by acid or a base. For example in the presence of base aldehydes and ketones react with hydrogen cyanide to form cyanohydrin.
What is the product formed when an aldehyde other than formaldehyde is treated with Grignard reagent?

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There are mainly four series of the transition metals, 3d series (Sc to Zn), 4d series (Y to Cd), 5d series (La and Hf to Hg) and 6d series which has Ac and elements from Rf to Cn. The two series of the inner transition metals; 4f (Ce to Lu) and 5f (Th to Lr) are known as lanthanoids and actinoids respectively. Their chemical properties are transitional between those of s and p-block elements. The transition metals (with the exception of Zn, Cd and Hg) are very hard and have low volatility. Their melting and boiling points are high. Transition metals have incomplete d subshell either in neutral atom or in their ions. With partly filled d orbitals these elements exhibit certain characteristic properties such as display of a variety of oxidation states, formation of coloured ions and entering into complex formation with a variety of ligands. The transition metals and their compounds are known for their catalytic activity.
Which of the following statements is correct?

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Carboxylic acids are the organic compounds which comprise of carboxyl functional group, -COOH. These are generally found in nature, some higher members are known as fatty acids as they occur in natural fats as esters of glycerol. They can be prepared from oxidation of alcohols and aldehydes, hydrolysis of nitriles and amides and Grignard reagents. They are stronger acids than simple phenols and alcohols. but weaker than mineral acids. Substituents affect the acidity of aliphatic and aromatic carboxylic acids. They undergo reactions involving cleavage of -OH and C-OH bond. Carboxylic acids having an alpha hydrogen get halogenated in the presence of red phosphorus to form alpha halo carboxylic acids. The reaction is known as Hell Volhard Zelinsky reaction. Besides these aromatic carboxylic acids undergo electrophilic substitution reactions. They are versatile and are employed in the manufacture of various useful compounds. For example, methanoic acid is used in rubber, textile, dyeing, leather and electroplating industries. Higher fatty acids are used in the manufacture of soaps and detergents. Esters of Benzoic acid are used in perfumery.
Which carboxylic acid will not undergo HVZ reaction?

Which of the following can be used as a froth stabiliser during ore concentration?

Which of the following statements are correct ?
(A) Glucocorticoids control the carbohydrate metabolism
(B) Testosterone is major female sex hormone
(C) Insulin is released in response to increase in blood sugar
(D) Hypothyroidism is caused by low level of thyroxine
(E) Mineralocorticoid is major male sex hormone
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Estradiol hormone is responsible for:

Salicylaldehyde can be prepared by treating phenol with

A spherical ice ball is melting at the rate of \(100 \pi \mathrm{~cm}^3 / \mathrm{min}\). The rate at which its radius is decreasing when its radius is 15 cm, is

Pick the correct structure for carbolic acid among the following compounds:

The product, when an alcoholic solution of sucrose is boiled with dilute hydrochloric acid or sulphuric acid is/are

A 12 pF capacitor is connected to a 50 V battery. The electrostatic energy stored in the capacitor is

Match List I with List II.

List-I	List-II
(A) Hoffmann bromamide reaction	I. Detection test for primary amines
(B) Carbylamine reaction	II. Hinsberg reagent
(C) Gabriel phthalimide synthesis	III. Amine with lesser number of carbon atoms
(D) Benzene sulphonyl chloride	IV. Reaction of phthalimide with KOH and R-X.

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