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\( \text{pH} \) of water is \( 7 \) at \( 25^\circ\text{C} \). If water is heated to \( 80^\circ\text{C} \), it’s \( \text{pH} \) will:

A weak acid \( \mathrm{HA} \) has degree of dissociation \( x \). Which option gives the correct expression of \( (\mathrm{pH} - \mathrm{p}K_a) \)?

The \( \text{pH} \) of a \( 0.01 \,\text{M} \) weak acid \( \mathrm{HX} \) \( (K_a = 4 \times 10^{-10}) \) is found to be \( 5 \). Now the acid solution is diluted with excess of water so that the \( \text{pH} \) of the solution changes to \( 6 \). The new concentration of the diluted weak acid is given as \( x \times 10^{-4} \,\text{M} \). The value of \( x \) is ________ (nearest integer)

One litre buffer solution was prepared by adding \(0.10\) \(\text{mol}\) each of \(NH_3\) and \(NH_4Cl\) in deionized water. The change in \(\mathrm{pH}\) on addition of \(0.05\) \(\text{mol}\) of \(HCl\) to the above solution is ______ \(\times 10^{-2}\). (Nearest integer)
Given: \(pK_b\) of \(NH_3 = 4.745\) and \(\log_{10} 3 = 0.477\)

The correct set of ions (aqueous solution) with same colour from the following is:

\( K_{sp} \) for \( \mathrm{Cr(OH)_3} \) is \( 1.6 \times 10^{-30} \). What is the molar solubility of this salt in water?

An aqueous solution of \( \mathrm{HCl} \) with pH \( 1.0 \) is diluted by adding equal volume of water (ignoring dissociation of water). The pH of \( \mathrm{HCl} \) solution would . (Given \( \log 2 = 0.30 \))

If \( 1 \, \text{mM} \) solution of ethylamine produces \( \text{pH} = 9 \), then the ionization constant (\( K_b \)) of ethylamine is \( 10^{-x} \). The value of \( x \) is __________ (nearest integer).[The degree of ionization of ethylamine can be neglected with respect to unity.]

The molar solubility(s) of zirconium phosphate with molecular formula \( (\mathrm{Zr}^{4+})_{3}(\mathrm{PO}_{4}^{3-})_{4} \) is given by relation:

If equal volumes of \( \text{AB}_2 \) and \( \text{XY} \) (both are salts) aqueous solutions are mixed, which of the following combination will give a precipitate of \( \text{AY}_2 \) at \( 300 \, \text{K} \)?
(Given \( K_{sp} \) (at \( 300 \, \text{K} \)) for \( \text{AY}_2 = 5.2 \times 10^{-7} \))

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JEE Main 2025 28th Jan Morning Shift

A weak acid \( \mathrm{HA} \) has degree of dissociation \( x \). Which option gives the correct expression of \( (\mathrm{pH} - \mathrm{p}K_a) \)?