Who is the former President of South Korea?

Which of the following elements has the highest electronegativity.

Which alloy is formed by mixing iron with carbon, nickel, and zinc?

Which of the following rock is not a sedimentary rock?

What term is used for atoms that have the same number of protons but different numbers of neutrons?

Which chemical compound is used in the indelible ink for elections?

Which of the following substances are ozone-depleting?

Select the correct answer from the code given below.

The gas usually causing explosions  in coal  mines  is-

Hydrogen exhibits properties similar to which groups in the periodic table?

What is the total number of carbon atoms in a molecule of butane?

Carbohydrates are organic compounds composed of which elements?