Which of the following species by definition has ZERO standard Molar enthalpy of formation at 298 K?
(A) Br2 (g) (B) CH4 (g) (C) Cl2 (g) (D) H2O (g) The Correct Answer is (C) Cl2 (g). Cl2... View Article
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Which factor is most responsible for the increase in boiling points of noble gases from He to Xe?
(A) Monoatomic nature (B) Increase in polarisability (C) Decrease in polarisability (D) Decrease in Ionisation energy The Correct Answer is... View Article
Which of the following alkali metals has the highest melting point?
(A) K (B) Li (C) Na (D) Rb The Correct Answer is (B) Li. Solution: Li has the highest melting... View Article
Assertion: Aquatic species are more comfortable in warm water than cold water. Reason: Different gases have different KH values at the same temperature.
(A) Both Assertion and Reason are false. (B) Assertion is true, but Reason is false. (C) Both Assertion and Reason... View Article
In CsCl type structure, the coordination number of Cs+ is Cl- respectively are:
(A) 6,6 (B) 6,8 (C) 8,6 (D) 8,8 The Correct Answer is (D) 8,8 Solution: In Cesium chloride [CsCl], caesium... View Article
Which of the following configurations is associated with the biggest jump between 2nd and 3rd I.E.?
(A) 1s2, 2s2, 2p1 (D) (B) 1s2, 2s2, 2p2 (A) (C) 1s2, 2s2, 2p6, 3s1 (B) (D) 1s2, 2s2, 2p6,... View Article
An organic compound contains carbon, hydrogen and oxygen. Its elemental analysis gave C, 38.71% and H, 9.67%. What would be the empirical formula of the compound?
(A) CHO (B) CH2O (C) CH3O (D) CH4O The Correct Answer is (C) CH3O Solution: The empirical formula is to... View Article
Assertion: Both Frenkel and Schottky defects are stoichiometric defects. Reason: Both defects change the density of the crystalline solid.
(A) Both Assertion and Reason are false. (B) Assertion is true, but Reason is false. (C) Both Assertion and Reason... View Article
Lithium forms body centred cubic structure. The length of the side of its unit cell is 351 pm. What will be the Atomic radius of lithium?
(A) 152 pm (B) 175 pm (C) 240 pm (D) 300 pm The Correct Answer is (A) 152 pm. Solution:... View Article
The rate constant for a chemical reaction taking place at 500k is expressed as k = A.e-1000. The activation energy (Ea) of the reaction is:
(A) 100 Kcal (B) 1000 Kcal (C) 10000 Kcal (D) 100000 Kcal The Correct Answer is (B) 1000 Kcal Solution:... View Article
What is the oxidation number of carbon in carbon suboxide [C3O2]?
(A) 2 (B) 2/3 (C) 4/3 (D) 10/3 The Correct Answer is (C) 4/3 Solution: The structure of carbon suboxide... View Article
Which of the following compounds can be used as antifreeze in automobile radiators?
(A) Glycol (B) Nitrophenol (C) Ethyl alcohol (D) Methyl alcohol The Correct Answer is (A) Glycol. Solution: Glycol can be... View Article
Which of the following compounds have higher boiling points?
(A) 1-chlorobutane (B) 1-chloropropane (C) Isopropyl Chloride (D) All of these The Correct Answer is (A) 1-chlorobutane. Solution: 1-chlorobutane has... View Article
The distance between an octahedral and tetrahedral void in fcc lattice is:
(A) \(\begin{array}{l}a\sqrt{3}\end{array} \) (B) \(\begin{array}{l}\frac{a\sqrt{3}}{2}\end{array} \) (C)\(\begin{array}{l} \frac{a\sqrt{3}}{4}\end{array} \) (D)\(\begin{array}{l} \frac{a\sqrt{3}}{6}\end{array} \) The Correct Answer is (C)\(\begin{array}{l} \frac{a\sqrt{3}}{4}\end{array} \). Solution:... View Article
How many pi bonds are present in the molecule of CH3 – CH = CH – C = CH?
(A) 2 bonds (B) 3 bonds (C) 8 bonds (D) 9 bonds The Correct Answer is (B) 3 bonds Solution:... View Article
How many sigma bonds are present in the molecule of dicyanoethene (CN−CH=CH−CN)?
(A) 2 sigma bonds (B) 3 sigma bonds (C) 5 sigma bonds (D) 7 sigma bonds The Correct Answer is... View Article
An element with the atomic number 19 will most likely combine chemically with the element whose atomic number is :
(A) 11 (B) 17 (C) 18 (D) 20 The Correct Answer is (B) 17 Solution: An element with the atomic... View Article
Assertion: PF5, SF6 and H2SO4 are examples of expanded octet molecules.Reason: Octet rule is not applicable to the second-period elements of the periodic table.
(A) Both Assertion and Reason are false. (B) Assertion is true, but Reason is false. (C) Both Assertion and Reason... View Article
Assertion: HNO3 is a stronger acid than HNO2. Reason: In HNO3 there are two nitrogen to oxygen bonds whereas in HNO2 there is only one.
(A) Both Assertion and Reason are false. (B) Assertion is true, but Reason is false. (C) Both Assertion and Reason... View Article
Which of the following oxide of iodine is used in the estimation of carbon monoxide?
(A) I2O4 (B) I2O5 (C) I2O6 (D) I2O7 The Correct Answer is (B) I2O5 Solution: Iodine peroxide [ I2O5] is... View Article
