Read the passage and answer the question :
A homologous series is a series of organic compounds which belong to the same family (i.e. possess the same functional group) and show similar chemical properties. The members of this series are called homologous and differ from each other by the number of CH2 units in the main carbon chain.
Q. What is the difference between two consecutive members in a homologous series in alkanes in terms of molecular mass and number of atoms of elements is: