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Chemistry · Some Basic Concepts of Chemistry
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Chemistry · Structure of atom
Consider the following statements related to atomic structure and sub-atomic particles: (I) J.J. Thomson proposed that the positive charge is uniformly distributed in a sphere with electrons embedded in it. (II) Rutherford's nuclear model accounts for the solar-system-like circular motion of electrons around the dense nucleus. (III) The charge on an electron was precisely measured by J.J. Thomson using cathode ray deflection. (IV) Isotopes share identical chemical properties due to having the same number of electrons and protons. Which combination of statements is correct?
Read answer →Chemistry · PYQ NEET UG 2022
Which one is NOT correct mathematical equation for Dalton’s Law of partial pressure? Here \( p \) = total pressure of gaseous mixture
Read answer →Chemistry · Classification of Elements and Periodicity in Properties
What is the formula of the compound formed between aluminium and sulphur?
Read answer →Chemistry · Some Basic Concepts of Chemistry
What is the mass per cent of oxygen in sodium sulphate (\( \text{Na}_2\text{SO}_4 \))? (Atomic masses: \( \text{Na} = 23, \text{S} = 32, \text{O} = 16 \))
Read answer →Chemistry · THERMODYNAMICS
Refer to the given figure showing three types of thermodynamic systems (a), (b), and (c). Which of the following statements correctly identifies the boundaries and exchanges?
Read answer →Chemistry · PYQ NEET UG 2024
Match List I with List II. List I (Conversion) A. 1 mol of \( H_2O \) to \( O_2 \) B. 1 mol of \( MnO_4^- \) to \( Mn^{2+} \) C. 1.5 mol of Ca from molten \( CaCl_2 \) D. 1 mol of FeO to \( Fe_2O_3 \) List II (Number of Faraday required) I. 3F II. 2F III. 1F IV. 5F Choose the correct answer from the options given below:
Read answer →Chemistry · PYQ NEET UG 2016(2)
Boric acid is an acid because its molecule
Read answer →Chemistry · Some Basic Concepts of Chemistry
Which of the following mixtures represents a homogeneous mixture?
Read answer →Chemistry · CHEMICAL BONDING AND MOLECULAR STRUCTURE
Given below are two statements: one is labelled as Assertion (A) and the other is labelled as Reason (R). Assertion (A): Two isolated hydrogen atoms do not form a bond when their total potential energy increases as they approach each other. Reason (R): A covalent bond between two atoms is formed only when the net attractive forces overcome the repulsive forces and the system acquires minimum potential energy. In the light of the above statements, choose the correct answer from the options given below:
Read answer →Chemistry · Some Basic Concepts of Chemistry
If the density of methanol is \( 0.793\text{ kg L}^{-1} \), what is its volume needed for making \( 2.5\text{ L} \) of its \( 0.25\text{ M} \) solution? (Molar mass = \( 32\text{ g mol}^{-1} \))
Read answer →Chemistry · Structure of atom
A cathode ray tube operates at a high voltage in a partially evacuated glass tube. In the absence of external fields, what is the nature of the path traveled by the cathode rays?
Read answer →Chemistry · Structure of atom
Calculate the wavelength of a light wave whose period is \( 2.0 \times 10^{-10} \text{ s} \).
Read answer →Chemistry · CHEMICAL BONDING AND MOLECULAR STRUCTURE
Match List-I with List-II: List-I (Molecule) List-II (Dipole moment in Debye) A \( \text{HF} \) I \( 0.23 \) B \( \text{H}_2\text{S} \) II \( 1.78 \) C \( \text{NH}_3 \) III \( 0.95 \) D \( \text{NF}_3 \) IV \( 1.47 \) Choose the correct answer from the options given below:
Read answer →Chemistry · CHEMICAL BONDING AND MOLECULAR STRUCTURE
The experimentally determined carbon-oxygen bond length in \( \text{CO}_2 \) is \( 115\text{ pm} \). This value is intermediate between which of the following standard bond lengths?
Read answer →Chemistry · Some Basic Concepts of Chemistry
How many moles of carbon dioxide (\( \text{CO}_2 \)) are required to be produced from the combustion of methane to obtain \( 22\text{ g} \) of \( \text{CO}_2 \)?
Read answer →Chemistry · PYQ NEET UG 2016(2)
The percentage of pyridine (\( \mathrm{C_5H_5N} \)) that forms pyridinium ion \( \mathrm{C_5H_5NH^+} \) in a \( 0.10\ \mathrm{M} \) aqueous pyridine solution is ________. (\( \mathrm{K_b} \) for \( \mathrm{C_5H_5N} = 1.7 \times 10^{-9} \))
Read answer →Chemistry · THERMODYNAMICS
For the formation reaction \( \text{H}_2(g) + \text{Br}_2(l) \to 2\text{HBr}(g) \), the reaction enthalpy is \( \Delta_r H^\ominus = -72.8\text{ kJ mol}^{-1} \). What is the standard molar enthalpy of formation (\( \Delta_f H^\ominus \)) of \( \text{HBr}(g) \)?
Read answer →Chemistry · Some Basic Concepts of Chemistry
In the macroscopic particle arrangement depicted below, what represents the primary driving factor for the phase transition from state (a) to state (b) and subsequently to state (c)?
Read answer →Chemistry · PYQ NEET UG 2026
Two moles of an ideal gas undergo free expansion from $10\text{ L}$ to $100\text{ L}$ at $300\text{ K}$. The values of $\Delta S_{\text{system}}$ and $\Delta S_{\text{surroundings}}$ are (R is universal gas constant)
Read answer →Chemistry · PYQ NEET UG 2023
The element expected to form largest ion to achieve the nearest noble gas configuration is:
Read answer →Chemistry · EQUILIBRIUM
What is the \( [\text{H}^+] \) concentration in a solution containing \( 0.05\text{ M} \) acetic acid and \( 0.05\text{ M} \) sodium acetate? (Given: \( K_a \text{ of } \text{CH}_3\text{COOH} = 1.8 \times 10^{-5} \))
Read answer →Chemistry · PYQ NEET UG 2020
Identify the CORRECT statement from the following:
Read answer →Chemistry · Some Basic Concepts of Chemistry
