An isotope refers to elements with the same atomic number but different numbers of neutrons.

He participated in the anti-war movement.

We are focusing on the research and development of new products.

Developmental dictatorship can bring about economic growth, but there are also issues of human rights violations.

He is a second-year high school student.

This factory manufactures iron using coke.

We have developed a new method to produce charcoal from wood.

My grandfather used to work in charcoal production.

He works digging out coal.

Ammonium carbonate is a compound commonly used in inorganic chemistry.