NEET (UG) Solved Papers Portal

Identify the correct statement about ClF₃ from the following options:

In a test tube containing a salt, a few drops of dilute H₂SO₄ was added, which gave colourless vapours having the smell of vinegar. The vapours turned the blue litmus paper red.
Identify the correct anion from the following:

At 298 K, a certain buffer solution contains equal concentrations of X⁻ and HX, K_b for X⁻ is 10⁻¹⁰.
What is the pH of this buffer solution?

Calculate emf of the half cell given below :
$$\text{Pt (s)} \mid \text{H}_2\text{(g, 2 atm)} \mid \text{HCl (aq, 0.02 M)}$$
$$E_{\text{H}_2/\text{H}^+}^\circ = 0\text{ (zero) V}$$
(Given: $$\frac{2.303 RT}{F} = 0.059$$, $$\log 2 = 0.3010$$)

The calculated 'spin-only' magnetic moment of Ti²⁺ (3d²) is :

Identify the incorrect statement from the following:

The correct formal charges on oxygen atoms numbered 2, 1 and 3 respectively are:
O₃ (ozone molecule) where atom 1 is the central oxygen, atom 2 is double-bonded, and atom 3 is single-bonded.

Phenolphthalein is used as an indicator for the titration of sodium hydroxide solution against a standard solution of oxalic acid. The colour change that is observed at an alkaline pH close to the equivalence point during this titration is:

When 1 dm³ of CO₂ gas is passed over hot coke the volume of gaseous mixture after complete reaction at STP becomes 1.4 dm³. The composition of the gaseous mixture at STP is:

The major product Z formed in the following sequence of reactions is:
$$\text{C}_2\text{H}_6 \xrightarrow{\text{Cl}_2 / \text{UV light}} \text{X (monochlorinated product)} \xrightarrow{\text{NH}_3} \text{Y} \xrightarrow{\text{(i) NaNO}_2 / \text{HCl}, \text{ (ii) H}_2\text{O}} \text{Z}$$

Given below is an expression for the rate constant of a first-order reaction occurring at a certain temperature, T (K).
$$\ln k = 14.34 - \frac{1.25 \times 10^4}{T}$$
The energy of activation in kcal mol⁻¹ for the reaction is:
(Given: k in s⁻¹, R = 1.987 cal mol⁻¹ K⁻¹)

Given below are certain reactions. Identify the reaction for which K_P ≠ K_C

Identify the incorrect statement from the following:

Mixture of chloroform and acetone forms a solution with negative deviation from Raoult's law due to:

The number of chlorine atoms present in the organic products X and Y of the following reactions, respectively, are:
$$\text{C}_6\text{H}_6 + 6\text{Cl}_2 \xrightarrow[\text{dark, cold}]{\text{Anhydr. AlCl}_3} \text{X}$$
$$\text{C}_6\text{H}_6 + 3\text{Cl}_2 \xrightarrow[500\text{ K}]{\text{UV}} \text{Y}$$

In angiosperms, root hairs arise from which one of the following regions of the root?

In which one of the following, the ovules are not enclosed by an ovary wall and remain exposed?

In the lac operon, the z gene codes for

Exploring molecular, genetic and species-level diversity for products of economic importance is called

Match List I with List II:

Match List I with List II:

Since the origin and diversification of life on Earth, there have been five episodes of mass extinction of species. How is the sixth extinction, which is in progress, different from the previous episodes?

Alpha-helix is found in which level of protein structure?

The main function of bulliform cells in grasses is

Identify the correct sequence of steps in each cycle of Polymerase Chain Reaction: