In the given question, which one of sets of the letter

What process is used to create a protective oxide layer on aluminum?

What did Archimedes determine after discovering the Archimedes principle?

Which element dominates the Earth's crust by percentage?

Potassium Permanganate is used for purifying drinking water, because it – 

Nitrous Oxide (N2O) is also known as –

Manganite is an ore/mineral of -

Which compound is commonly used in the production of heat-resistant bricks for fireplaces and furnaces?

Which gas is most abundant in the Earth's atmosphere?

Protons were discovered by

The fuel that is used in modern submarines is -