Question

HNO3, NaOH, AgNO3, and CaCl2.which turns litmus paper red?

Answer 1

Nitric acid (HNO3) is the substance that turns litmus paper red, indicating it is an acid. Neither AgNO3 nor CaCl2 would change the litmus paper color as they are salts, and NaOH would turn red litmus paper blue because it's a base.

Step-by-step explanation:

The chemical substances in question are HNO3 (nitric acid), NaOH (sodium hydroxide), AgNO3 (silver nitrate), and CaCl2 (calcium chloride). To determine which substance turns litmus paper red, one must understand the properties of acids and bases. Acids, such as HNO3, turn blue litmus paper red. In contrast, bases, such as NaOH, turn red litmus paper blue. Neither AgNO3 nor CaCl2 will affect the litmus paper in this manner, as they are salts and do not exhibit acidic or basic properties when dissolved in water. Therefore, the only substance that will turn litmus paper red among the ones listed is nitric acid (HNO3), as it is an acid.

Answer 2

The litmus paper test is used to identify if a solution is acidic or basic, it works by interacting with the solution and changing its color according to the pH of the solution, if the paper turns red, this means we have an acidic solution, and if the paper turns blue, this means that we have a basic solution.

In our question the only acid present is HNO3, so this will be the only one to turn the litmus paper red

NaOH is a base

AgNO3 and CaCl2 both are salts.