Skip to content
Login Register

CHEMISTRY

Latest questions in this category.

45 questions

CHEMISTRY

How many molecules are in 4 g of H₂? (Molar mass = 2 g/mol, Avogadro number = 6.022 × 10²³)

Given: How many molecules are in 4 g of H₂? (Molar mass = 2 g/mol, Avogadro number = 6.022 × 10²³) These values define the system as per NCERT data. Formula: Moles = 4 / 2 = 2 mol. This is the standard NCERT relation for this phenomenon. Substitution & Calculation: Molecules = 2 × 6.022 × 10²³ = 1.2044 × 10²⁴. Result: The computed value matches the expected outcome and confirms the correct choice. Units and powers like J kg⁻¹ K⁻¹, m/s², 10⁻⁵ 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.

View Details
CHEMISTRY

Which of the following is an industrial application of KMnOâ‚„ ?

KMnOâ‚„ is used for bleaching textiles (wool, cotton, silk) due to its strong oxidizing power. 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.

View Details
CHEMISTRY

Which of the following amino acids is not optically active?

Glycine lacks an asymmetric carbon atom (its side chain is -H), making it the only naturally occurring α-amino acid that is not optically active. 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.

View Details
CHEMISTRY

What is the product when CH₃CH₂NH₂ reacts with excess CH₃CH₂Br ?

With excess CH₃CH₂Br, CH₃CH₂NH₂ undergoes exhaustive alkylation to form the tertiary amine (CH₃CH₂)3N (triethylamine). 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.

View Details
CHEMISTRY

Which reaction converts benzene to benzophenone?

Friedel-Crafts acylation introduces a ketone functional group into benzene. 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.

View Details
CHEMISTRY

Which of the following alcohols will show a positive iodoform test?

Alcohols with the structure CH ₃ -C(OH)-R (where R can be H or any alkyl group) give a positive iodoform test. 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.

View Details
CHEMISTRY

Which ligand is bidentate?

A bidentate ligand binds through two donor atoms. H₂NCH₂CH₂NH₂ (ethane-1, 2-diamine or en) has two nitrogen atoms that can coordinate, making it bidentate, unlike NH₃, Cl^-, or H₂O, which are unidentate.

Ref: NCERT Chemistry Textbook for Class XI and XII, Chapter: Relevant Chemistry topic covering principles and examples as per NCERT.

View Details
CHEMISTRY

Which of the following lanthanoids exhibits a +4 oxidation state due to its noble gas configuration?

Given: Which of the following lanthanoids exhibits a +4 oxidation state due to its noble gas configuration? These values define the system as per NCERT data. Formula: Cerium (Ce, Z = 58) forms Ce^{4+ with 4f⁰ (noble gas-like), making it stable in this state.. This is the standard NCERT relation for this phenomenon. Substitution & Calculation: Substituting values like 1.2 × 10⁻⁵, 236 J kg⁻¹ K⁻¹, CH₃CH₂NH₂ 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 kg⁻¹ K⁻¹, m/s², 10⁻⁵ 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.

View Details
CHEMISTRY

Which element with atomic number 114 belongs to which block?

Given: Which element with atomic number 114 belongs to which block? These values define the system as per NCERT data. Formula: Flerovium (Z=114) has the configuration [Rn]5f¹⁴6d¹⁰7s²7p², with the last electron in 7p, placing it in the p-block.. This is the standard NCERT relation for this phenomenon. Substitution & Calculation: Substituting values like 1.2 × 10⁻⁵, 236 J kg⁻¹ K⁻¹, CH₃CH₂NH₂ 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 kg⁻¹ K⁻¹, m/s², 10⁻⁵ are properly used as per NCERT.

Ref: NCERT Chemistry Textbook for Class XI and XII, Chapter: p-Block, d and f Block Elements and Coordination Compounds, Topic: Properties of block elements and coordination chemistry.

View Details