Which is the chemically most active element?
Fluorine is the chemically most active element due to its small size and high electronegativity.
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What are the characteristics of a chemical change?
Some of the characteristics of chemical change are: A new substance is formed Changes occur in the composition of the... View Article
Name a hydrogen containing compound which is not an acid but a salt.
Methane (CH4) is a hydrogen containing compound which is not an acid but a salt.
The following quantum numbers are possible for how many orbital(s): n = 3, l = 2, m = +2
(A) 1(B) 2(C) 3(D) 4Correct option: (A) 1Given, n = 3, l = 2, m = +2These numbers represents an... View Article
The process with negative entropy change is
(1) Dissociation of CaSO4(s) to CaO(s) and SO3(g) (2) Dissolution of iodine in water (3) Synthesis of ammonia from N2... View Article
Calculate the mass of an atom of silver(atomic mass = 108).
1 mole = 6.022 x 1023 molecules Mass of 6.022 x 1023 atoms of silver (Ag) = 108 g Mass... View Article
By adding common salt to distilled water makes it
(a) Good conductor(b) Insulator(c) Semiconductor(d) None of theseCorrect option: (a) Good conductorBy adding common salt to distilled water makes it... View Article
Ammonium dichromate on heating gives
Ammonium dichromate on heating gives chromium(III) oxide and nitrogen gas. This can be represented as: (NH4)2Cr2O7(s) → Cr2O3(s) + N2(g)... View Article
On heating blue coloured powder of copper (II) nitrate in a boiling tube, copper oxide (black) oxygen gas and a brown gas X is formed. (1) Write a balanced chemical equation of the reaction (2) Identify the brown gas X evolved (3) Identify the type of reaction (4) What could be the pH range of the aqueous solution of the gas X?
Answer: Chemical equations are symbolic representations of chemical reactions in which the reactants and the products are expressed in terms... View Article
Floods can be prevented by
(a) afforestation (b) removing top soil (c) deforestation (d)agricultureCorrect option: (a) afforestation Floods can be prevented by afforestation.
Find the oxidation number of carbon in glucose C₆H₁₂O₆.
Let’s consider the oxidation number of C in C6H12O6 as xWe know that the oxidation of H is -1 and... View Article
How many moles of lead (II) chloride will be formed from a reaction between 6.5 g PbO and 3.2 g HCl?
Answer: 0.029 mol The atomic mass of PbO = 223 The number of moles in 6.5 g of PbO =... View Article
What is the coordination number of an atom?
The coordination number of an atom in a given molecule or a crystal refers to the total number of atoms,... View Article
BaCl₂(aq)+Na₂SO₄(aq) → BaSO₄(s) + 2NaCl(aq) The above reaction involves which type of reaction: (a) Displacement (b) Precipitation (c) Combination (d) Double displacement
Answer: Both (b) and (d) A precipitate of barium sulphate is obtained so it’s a precipitation reaction. Also, when two... View Article
Density of a 2.05 M solution of acetic acid in water is 102 g/ml. The molality of the solution is:
Let’s consider the volume of solution of acetic acid and water as1000 mlSo, we have 1.02 gm of acetic acid... View Article
The tribasic acid is a) H₃PO₄ b) H₃PO₃ c) H₃PO₂ d) HPO₃
Answer: a) H3PO4 That’s because P-H bonds are not ionizable to give H+ whereas, the H atoms which are attached... View Article
The role of a catalyst is to change
The role of a catalyst is to change the activation energy of reaction.
Flourobenzene C6H5F can be synthesised in the laboratory
Fluorobenzene (C6H5F) can be synthesized in the laboratory from aniline by diazotisation followed by heating the diazonium salt with HBF4.... View Article
Lyophilic sols are more stable than lyophobic sols because
The stability of lyophilic sols is due to the presence of a charge and the solvation of colloidal particles. On... View Article
Difference between Inductive Effect and Mesomeric Effect
Inductive Effect Mesomeric Effect It operates in saturated compounds. It operates in unsaturated compounds. The electron pair is slightly displaced... View Article
