Latest questions in this category.
Atomic radius decreases across a period. In the third period (Na to Ar), Cl has the smallest radius due to highest nuclear charge. This follows from NCERT principle where the relation explains the outcome clearly for students in simple steps.
Ref: NCERT Chemistry Textbook for Class XI and XII, Chapter: Relevant Chemistry topic covering principles and examples as per NCERT.
In CH₃CH₂OCH₃, there are 9 single bonds: 8 C-H, 1 C-C, and 2 C-O. Each single bond is a sigma bond, totaling 9. This follows from NCERT principle where the relation explains the outcome clearly for students in simple steps.
Ref: NCERT Chemistry Textbook for Class XI and XII, Chapter: Some Basic Concepts, Structure of Atom and Periodicity, Topic: Mole concept, atomic models and periodic trends.
Given: What is the mass of nickel deposited at the cathode when a 5 A current flows through Ni(NO₃)â‚‚ solution for 20 minutes? (Molar mass of Ni = 58.7 g/mol, F = 96500 C/mol) These values define the system as per NCERT data. Formula: Q = 5 × 1200 = 6000 C. This is the standard NCERT relation for this phenomenon. Substitution & Calculation: For Ni²⺠+ 2e⻠→ Ni(s), 2F (193000 C) deposits 58.7 g. Mass = 58.7 × 6000/193000 approx 1.824 g . Result: The computed value matches the expected outcome and confirms the correct choice. Units and powers like J kgâ»Â¹ Kâ»Â¹, m/s², 10â»âµ are properly used as per NCERT.
Ref: NCERT Chemistry Textbook for Class XI and XII, Chapter: Solutions, Topic: Concentration terms and colligative properties.
Given: What is the atomic number of an element with 3 electrons in its 2p subshell? These values define the system as per NCERT data. Formula: Total electrons = 2 + 2 + 3 = 7, so Z = 7 (nitrogen).. This is the standard NCERT relation for this phenomenon. Substitution & Calculation: Configuration up to 2p with 3 electrons: 1s² 2s² 2p³. Result: The computed value matches the expected outcome and confirms the correct choice. Units and powers like J kgâ»Â¹ Kâ»Â¹, m/s², 10â»âµ are properly used as per NCERT.
Ref: NCERT Chemistry Textbook for Class XI and XII, Chapter: Relevant Chemistry topic covering principles and examples as per NCERT.
Given: What is the number of unpaired electrons in [Mn(Hâ‚‚O)6]^{2+ ? These values define the system as per NCERT data. Formula: Mn²⺠( dâµ ) with weak field Hâ‚‚O in an octahedral field is high spin ( t_{2g³ e_g² ), with 5 unpaired electrons.. This is the standard NCERT relation for this phenomenon. Substitution & Calculation: Substituting values like 1.2 × 10â»âµ, 236 J kgâ»Â¹ Kâ»Â¹, CH₃CHâ‚‚NHâ‚‚ etc. into the formula and simplifying step by step. Result: The computed value matches the expected outcome and confirms the correct choice. Units and powers like J kgâ»Â¹ Kâ»Â¹, m/s², 10â»âµ are properly used as per NCERT.
Ref: NCERT Chemistry Textbook for Class XI and XII, Chapter: Some Basic Concepts, Structure of Atom and Periodicity, Topic: Mole concept, atomic models and periodic trends.
Propan-2-amine with excess CH₃I forms a quaternary salt ( (CH₃)2CHN(CH₃)3+I- ), which with AgOH undergoes elimination to yield (CH₃)2CHN(CH₃)2 .
Ref: NCERT Chemistry Textbook for Class XI and XII, Chapter: Relevant Chemistry topic covering principles and examples as per NCERT.
Given: How many grams of Oâ‚‚ are produced from 49 g of Hâ‚‚Oâ‚‚ in the reaction 2Hâ‚‚Oâ‚‚ -> 2Hâ‚‚O + Oâ‚‚ ? (Atomic masses: H = 1, O = 16) These values define the system as per NCERT data. Formula: Molar mass of Hâ‚‚Oâ‚‚ = 34 g/mol. This is the standard NCERT relation for this phenomenon. Substitution & Calculation: Moles of Hâ‚‚Oâ‚‚ = 49 / 34 ≈ 1.441 mol. 2 mol Hâ‚‚Oâ‚‚ produce 1 mol Oâ‚‚. Moles of Oâ‚‚ = 1.441 / 2 ≈ 0.7205 mol. Mass = 0.7205 × 32 ≈ 23.06 g ≈ 23 g. Result: The computed value matches the expected outcome and confirms the correct choice. Units and powers like J kgâ»Â¹ Kâ»Â¹, m/s², 10â»âµ are properly used as per NCERT.
Ref: NCERT Chemistry Textbook for Class XI and XII, Chapter: Some Basic Concepts, Structure of Atom and Periodicity, Topic: Mole concept, atomic models and periodic trends.
Ethene reacts with bromine in CClâ‚„ to form 1, 2-dibromoethane. This follows from NCERT principle where the relation explains the outcome clearly for students in simple steps.
Ref: NCERT Chemistry Textbook for Class XI and XII, Chapter: Some Basic Concepts, Structure of Atom and Periodicity, Topic: Mole concept, atomic models and periodic trends.
Soda lime (NaOH + CaO) is commonly used to remove the carboxyl group from carboxylic acids, forming hydrocarbons. This follows from NCERT principle where the relation explains the outcome clearly for students in simple steps.
Ref: NCERT Chemistry Textbook for Class XI and XII, Chapter: Some Basic Concepts, Structure of Atom and Periodicity, Topic: Mole concept, atomic models and periodic trends.
Wurtz reaction involves the reaction of alkyl halides with sodium metal in dry ether to form alkanes. This follows from NCERT principle where the relation explains the outcome clearly for students in simple steps.
Ref: NCERT Chemistry Textbook for Class XI and XII, Chapter: Some Basic Concepts, Structure of Atom and Periodicity, Topic: Mole concept, atomic models and periodic trends.
Na goes from 0 in elemental form to +1 in NaOH, an increase of +1, indicating oxidation. This follows from NCERT principle where the relation explains the outcome clearly for students in simple steps.
Ref: NCERT Chemistry Textbook for Class XI and XII, Chapter: Some Basic Concepts, Structure of Atom and Periodicity, Topic: Mole concept, atomic models and periodic trends.
Given: The reaction 2X -> Y has an average rate of formation of Y as 4.0 × 10â»â´ mol L^{-1 min^{-1 . What is the rate of disappearance of X in the same units? These values define the system as per NCERT data. Formula: Rate = -1/2 fracΔ[X]Δ t = fracΔ[Y]Δ t. This is the standard NCERT relation for this phenomenon. Substitution & Calculation: fracΔ[Y]Δ t = 4.0 × 10â»â´, so -fracΔ[X]Δ t = 2 × 4.0 × 10â»â´= 8.0 × 10â»â´. Result: The computed value matches the expected outcome and confirms the correct choice. Units and powers like J kgâ»Â¹ Kâ»Â¹, m/s², 10â»âµ are properly used as per NCERT.
Ref: NCERT Chemistry Textbook for Class XI and XII, Chapter: Relevant Chemistry topic covering principles and examples as per NCERT.
