The correct options are as follows:
1. A.
A synthesis reaction is a type of reaction in which two or more reactants combine together to form only one product. Synthesis reaction always release energy in form of light and heat, therefore, they are usually exothermic reactions. In the option given in A, nitrogen and nitrogen combine together to form ammonia; this is a synthesis reaction.
2. D
A radioactive half life refers to the amount of time it will take for half of an original radioactive isotope to decay.
In the question given above, the half life of the element is 1000. Thus, in 1000 years only half of the original amount will remain. In another 1000 years only 1/4 of the original amount will remain and in another 1000 years only 1/8 of the original amount will remain. Therefore, it will take 3 half lives before 1/8 of the original sample remain.<span />
A. cyclohexyne is the answer
When sodium amide i.e.
reacts with water i.e. 
results in the formation of sodium hydroxide i.e. 
and ammonia 
.
The chemical reaction is given by:
Now, when ammonia i.e. reacts with water results in the formation of ammonium hydroxide i.e. 
The chemical reaction is given by:
Thus, the products of the above reactions are ammonia and ammonium hydroxide (without sodium ion).
The structures of the products are shown in figure (1): ammonium hydroxide and figure (2) ammonia.
There are 2 moles in 8 grams
