An unknown compound melting at 134oC was suspected to be either aspirin (mp 135oC) or urea (mp 133oC). How can you determine whether the unknown was identical to one of these two by using the melting point technique only? Explain with your own words.'

Answer is in the explanation

Explanation:

Melting point is a property of chemical substances. It is used, with another experiments, to identify an unknown.

All measurements have uncertainty. That means the probability of melting point of the unknown to be 135°C or 133°C is equal. But with this measurement you can discard another substances with different melting points.

To identify a substance you require, at least, 3 different techniques. For example, you can smell the unknown (Urea has a strong smell but aspirin has not)

the correct option is c.

isotopes refers to different forms of the same element with the same atomic number but different mass number as a result of difference in their neutron numbers. isotopes have different relative atomic mass but share the same chemical properties.