TN State Board 12th Chemistry Question Paper 2023

Milk of Magnesia is a suspension of magnesium hydroxide, $Mg(OH)_2$. It acts as an antacid by neutralizing excess hydrochloric acid in the stomach. Tranquilizers are for mental stress, analgesics for pain relief, and anaesthetics for inducing insensibility, making them incorrect.

A catalyst provides an alternative reaction pathway with a lower activation energy ($E_a$), thereby increasing the reaction rate. It does not affect the thermodynamic properties like entropy, internal energy, or enthalpy of the reactants or products.

The Hall-Heroult process is specifically used for the electrolytic reduction of pure alumina ($Al_2O_3$) dissolved in molten cryolite ($Na_3AlF_6$) to extract aluminium (Al).

The magnetic moment $\mu = \sqrt{n(n+2)} BM$. For $\mu = 1.73 BM$, $n = 1$ (one unpaired electron). In $[Cu(NH_3)_4]^{2+}$, the $Cu^{2+}$ ion is $d^9$, which leaves one unpaired electron in the $3d_{x^2-y^2}$ orbital, matching the magnetic moment. $TiCl_4$ ($d^0$), $[Ni(CN)_4]^{2-}$ ($d^8$ square planar, diamagnetic), and $[CoCl_4]^{2-}$ ($d^7$, 3 unpaired electrons) do not fit.

A gel is a colloidal system where a liquid is dispersed in a solid. Butter is a perfect example of a gel. Other options are incorrectly matched (e.g., whipped cream is foam, not sol).