An alkene on ozonolysis gives methanal as one of the products. Its structure is:

1.  
 2.   

3.   
4.   

Which of the following is a free radical substitution reaction ?

1. Benzene with Br₂/AlCl₃

2. Acetylene with HBr

3. Methane with Br₂/hv

4. Propene with HBr/(C₆H₅COO)₂

The alkane that gives only one monochloro product on chlorination with $C{l}_2$ in presence of diffused sunlight is -

1. 2,2,-dimethylbutane

2. neopentane

3. n-pentane

4. Isopentane

The compound obtained by addition of water to an alkyne having more than two carbons, in the presence of \(HgSO_4 \) and dilute \(H_2SO_4\) at 333K is- 

1. a vicinal diol 
2. an aldehyde 
3. an alcohol 
4. a ketone