NEET doubts
500 doubts found
What is the difference between orbit and orbital?
An orbit is a fixed Bohr path (outdated); an orbital is a 3-D region of high probability for finding an electron.
What does “Hydrogen bonding” actually mean in Chemical Bonding & Molecular Structure, and why does it matter for NEET?
a strong dipole attraction when H is bonded to N, O or F.
What is the difference between enthalpy and entropy?
Enthalpy is about heat content/energy; entropy is about disorder — spontaneity balances the two through ΔG.
What is the difference between K_c and K_p?
K_c uses molar concentrations; K_p uses partial pressures — they're related by K_p = K_c(RT)^Δn for gases.
How is Redox Reactions tested in NEET, and what should I focus on?
Prioritise the core ideas: Oxidation and reduction, Oxidation number, Oxidising and reducing agents.
What is the difference between atomic radius and ionization energy?
As atomic radius decreases across a period, ionization energy increases — smaller atoms hold their electrons more tightly.
What is the difference between order and molecularity?
Order is experimental and can be zero or fractional; molecularity is the count of species in an elementary step and is always a whole number.
What is the difference between galvanic cell and electrolytic cell?
A galvanic cell produces electricity from a spontaneous reaction; an electrolytic cell consumes electricity to force a non-spontaneous one.
What is the difference between electrophile and nucleophile?
An electrophile accepts an electron pair (e.g. H⁺, NO₂⁺); a nucleophile donates one (e.g. OH⁻, NH₃).
What is the difference between saturated hydrocarbon and unsaturated hydrocarbon?
Saturated means maximum hydrogens and only single bonds; unsaturated has double/triple bonds and fewer hydrogens.
What is the difference between molarity and molality?
Molarity is per litre of solution (temperature-dependent); molality is per kg of solvent (temperature-independent).
What is the difference between shell and subshell?
A shell is a principal energy level (n); a subshell (s, p, d, f) is a division within a shell.
I keep getting “Hydrogen bonding” questions wrong in Chemical Bonding & Molecular Structure. What's the trap?
treating hydrogen bonds as ordinary covalent bonds.
What is the difference between exothermic reaction and endothermic reaction?
Exothermic releases heat (ΔH<0, surroundings warm); endothermic absorbs heat (ΔH>0, surroundings cool).
What is the difference between strong acid and weak acid?
A strong acid ionises completely (HCl); a weak acid ionises only partly (CH₃COOH) and has an equilibrium.
What are the most common mistakes students make in Redox Reactions?
the oxidising agent is itself reduced and the reducing agent is itself oxidised — name by what they DO to the other species.
What is the difference between metals and non-metals?
Metals lose electrons easily (low ionization energy, form cations); non-metals gain electrons (high electronegativity, form anions).
What is the difference between rate and rate constant?
Rate depends on concentration and changes as the reaction proceeds; the rate constant k is fixed at a given temperature.
What is the difference between anode and cathode?
Oxidation occurs at the anode and reduction at the cathode — in every cell, regardless of the terminal signs.
What is the difference between inductive effect and resonance effect?
The inductive effect works through sigma bonds and fades with distance; resonance works through pi systems and can act over long conjugation.
How is Hydrocarbons tested in NEET, and what should I focus on?
Prioritise the core ideas: Saturation, Markovnikov's rule, Aromaticity.
What is the difference between atomic mass and molar mass?
Atomic mass is for one atom (in u); molar mass is for one mole of them (in g/mol) — same number, different units.
What is the difference between Aufbau principle and Hund's rule?
Aufbau decides the ORDER subshells fill (low to high energy); Hund decides HOW electrons spread within a subshell (singly, same spin).
What is the difference between ionic bond and covalent bond?
An ionic bond transfers electrons (metal + non-metal, forms ions); a covalent bond shares electrons (between non-metals).