Answer:
The methyl group will already be present
Explanation:
You want to make 1-methyl-4-nitrobenzene.
The question is, "Do I start with the methyl group on the ring and then nitrate, or do I start with the nitro group on the ring and then add the methyl group?"
The methyl group is activating and ortho, para directing.
The nitro group is deactivating and meta directing.
You want a para-substituted product, so you choose to nitrate toluene, as in the reaction scheme below.
Answer:- 0.134 seconds
Solution:- The speed is given as and the circumference is 24900 miles which is same as the distance light have to covered. It asks to calculate the time required to cover this distance by the light.
We need to do unit conversion from miles to meter as the speed is given in meter per second.
1 mile = 1609.34 meter
So,
= 40072566 meters
Know that,
It's rearranged to time as,
Let's plug in the values in it:
= 0.134 seconds
So, the light would take 0.134 seconds to travel the mentioned speed. The answer without the unit is 0.134.