In the following reaction:
$\text{Aldehyde} + \text{Alcohol} \xrightarrow{HCl} \text{Acetal}$
$HCHO \qquad ^tBuOH$
$CH_3CHO \qquad MeOH$
The best combination for the formation of acetal is:

Match the following:

$A$. Lucas reagent	$I$. $SnCl_2 + HCl$
$B$. Clemmensen reagent	$II$. $[Ag(NH_3)_2]^+$
$C$. Tollen's reagent	$III$. Anhydrous $ZnCl_2 + conc. HCl$
$D$. Stephen reagent	$IV$. $Zn-Hg/HCl$

Identify the product $A$ in the following reaction:
$1$-phenylcyclohex-$1$-en-$1$-one $\xrightarrow[(2) H^+]{(1) PhMgBr/CuCl} (A) (C_{19}H_{20}O)$

Which is the major product formed when acetone is heated with iodine and potassium hydroxide?

Identify the major product of the following reaction:

You have two $C_6H_{10}O$ ketones,$I$ and $II$. Both are optically active,but $I$ is racemized by treatment with acid and $II$ is not. Wolff-Kishner reduction of both ketones gives the same achiral hydrocarbon,formula $C_6H_{12}$. What reasonable structures may be assigned to $I$ and $II$ respectively?