JEE Main 2026

Identify A, B, and C in this Lead ( $Pb$ ) reaction sequence: 1. $PbCl_2 + K_2CrO_4 \rightarrow \mathbf{A} (\text{Yellow}) + KCl$ 2. $$\math...

Why does the white precipitate of $PbSO_4$ dissolve when Ammonium Acetate ( $CH_3COONH_4$ ) is added?

Compare the Hybridization and Geometry of: 1. $[NiCl_4]^{2-}$ 2. $[Ni(CN)_4]^{2-}$ 3. $[Ni(CO)_4]$

Predict the geometry of $[PtCl_4]^{2-}$ and $[PdCl_4]^{2-}$ . (Hint: How does it differ from $[NiCl_4]^{2-}$ ?)

Which of the following molecules are Tetrahedral? $SF_4, \ XeF_4, \ SeF_4, \ [NiCl_4]^{2-}, \ CH_4$

Complete the disproportionation reaction of Manganate ion in acidic medium: $3MnO_4^{2-} + 4H^+ \rightarrow \_\_\_\_\_\_ + \_\_\_\_\_\_ + 2H_2O$

Correct the order of Electron Affinity (EA) for Group 17: $F > Cl > Br > I$ (True or False?)

Arrange these oxides in decreasing order of Basic Nature: $Al_2O_3, \ Na_2O, \ K_2O, \ MgO$

Identify the Amphoteric Oxides in Group 14: $CO, \ CO_2, \ SiO_2, \ GeO_2, \ SnO, \ SnO_2, \ PbO, \ PbO_2$

Which pair is Diamagnetic? A) $[Ni(CO)_4]$ and $[NiCl_4]^{2-}$ B) $[Ni(CO)_4]$ and $[Ni(CN)_4]^{2-}$

Classify these Group 14 oxides as Acidic or Amphoteric: $GeO, \ GeO_2, \ SnO, \ SnO_2, \ PbO, \ PbO_2$

What is the common feature of these molecules? $AlCl_3, \ BH_3, \ BeH_2, \ NO_2$

Quick Calc: $14 \text{ g}$ Calcium reacts with excess $HCl$ . Calculate moles of $H_2$ evolved. ( $Ca = 40$ )

Identify A, B, C (Chromyl Chloride Test): 1. $NaCl + K_2Cr_2O_7 + H^+ \rightarrow \mathbf{A}$ (Red Vapor) 2. $$\mathbf{A} + NaOH \rightarrow \ma...

$CrO_5$ Structure Check: 1. Oxidation State of $Cr$ ? 2. Number of Peroxide linkages? 3. Shape name?

True/False Check: 1. Glycine has a chiral center. 2. Proline has a 6-membered ring. 3. Cysteine contains Sulfur.

Identify the type of Isomerism: 1. Propanal & Propanone 2. Ethoxy ethane & Methoxy propane 3. Pentane & 2,2-dimethyl propane

Does But-2-ene show Optical Isomerism? Explain.

Identify the isomerism between: But-2-ene and But-1-ene

Formula for % Sulfur in Carius Method. (Using $BaSO_4$ mass)

Calc Practice: $0.75 \text{ g}$ organic compound gives $1.2 \text{ g} \\ BaSO_4$ . Find % of Sulfur.

Shortcut Formula: Find $\Lambda_m^\infty$ for a weak acid $HX$ given only Conductivity ( $\kappa$ ) and pH. (Ignore C)

Unit Conversion: Convert $60,000 \text{ S cm}^2 \text{ mol}^{-1}$to SI units ($\text{S m}^2 \text{ mol}^{-1}$ ).

Identify the Tetrahedral species: $NH_4^+, \ XeF_4, \ BF_3, \ [Ni(CO)_4]$

Why is $[PtCl_4]^{2-}$ Square Planar while$[NiCl_4]^{2-}$is Tetrahedral?<br>(Both$d^8$+ weak ligand)

Predict geometry & hybridization of $[Cu(NH_3)_4]^{2+}$ .

Compare the shapes of $XeF_4$ and $BF_3$ .

$[NiCl_4]^{2-}$Properties: 1. Hybridization? 2. Magnetic Nature? 3. Geometry?