Choose the correct answers to the questions from the given options. Ammonia gas is passed through quicklime and then collected in a jar. Red and blue litmus papers are placed in the jar. W, X, Y and Z are the four observations. Which of the above observations correctly shows the reaction of the litmus papers to ammonia? | | Red litmus paper | Blue litmus paper | | :---: | :---: | :---: | | $\mathbf{W}$ | turns blue | remains blue | | $\mathbf{X}$ | remains red | remains blue | | $\mathbf{Y}$ | remains red | turns red | | $\mathbf{Z}$ | turns blue | turns red |

Explanation

Ammonia is a base and does not change the color of blue litmus paper, but it turns red litmus paper blue.