Which one of the following substances is used in the preservation of food stuff?

Which one of the following is used in the manufacture of soaps?

Which chemical substance is used for making rat poison?

Which one of the following living organisms gives litmus?

Which of the following is an example of herbicide?

A student studies that a soap molecule has two ends, one of which is an ionic end and the other is carbon chain. Which of the following option explains the interaction of soap molecule with oil?