AS Problem Collection¶

9701_w22_qp_12¶

Wrong Ans	C
Correct Ans	D
Explain	The strength of metal bonds is decided by the number of delocalized electrons

Wrong Ans	D
Correct Ans	C
Explain	$AgCl$ dissolves in ammonia to form $[Ag(NH_3)_2]^+$ ; $AgI$ does not solve in ammonia

Wrong Ans	B
Correct Ans	D
Explain	Alcohol's corresponding carboxylic acid has stronger H-bond than itself. Aldehydes and ketones do not have H-bonds.

Wrong Ans	1, 2
Correct Ans	1, 2, 3
Explain	The total area represents the total number of particles

Wrong Ans	C
Correct Ans	A
Explain	As solid, $AlCl3$ forms giant lattice. As liquid and vapor (< 400℃), it forms $Al2Cl6$ dimer. As vapor (> 400℃), it forms $AlCl3$ monomer.

Extra:

$SiCl_4 + 2H_2O \rightarrow 2SiO_2 + 4HCl$

$SiCl_4 + 4H_2O \rightarrow H_4SiO_4 + 4HCl$

Ground state: lowest possible energy state

2NaBr+2H2SO4→Br2+SO2+Na2SO4+2H2O

Wrong Ans	A
Correct Ans	D
Explain	$H_2SO_4$ opens $-COO-$ of the bottom right ring; $KMnO_4$ add OH to each end of $C=C$ . $KMnO_4$ does not provide O so alcohol is not oxidized to aldehyde or ketone, but $K_2Cr_2O_7$ can

Wrong Ans	B
Correct Ans	A
Explain	Saturated hexane ring is not planar but twisted. Benzane ring is planar.

Wrong Ans	A
Correct Ans	C
Explain	Enthalpy change is analyzed under room condition (298 K + 100kPa)

Wrong Ans	D
Correct Ans	B
Explain	Does not directly linked to the formation photochemical smog. Though, $NO_x$ + Volatile Organic Compounds $\xrightarrow{\text{sunlight}}$ photochemical smog.

Wrong Ans	C
Correct Ans	D
Explain	The intermediate is $R_2C(O^-)CN$ , with no $-OH$ .

Wrong Ans	X
Correct Ans	2, 3
Explain	For 2 and 3, though the equilibrium moves to the left/does not move, the concentration increases, so the rate of change of the forward reaction increases.

Wrong Ans	B
Correct Ans	A
Explain	NaOH(ethanol) can only be used in dehydrohalogenation, removing HX. To dehydrate, use conc. H₂SO₄.