How did the element hydrogen get its name?

Calculate the mass percentage of the element oxygen in hydrogen peroxide.

How does food get its taste?

Name the element with highest ionization enthalpy.

What is valency of an element? How does it vary with respect to hydrogen in the third period.

Which period starts with M main shell? Name the sub-shells in it? How many elements are there in this period ? Name any two elements in it ?

Study the pictures. How does a grasshopper get its energy?