What is the pH range in which phenolphthalein is colourless ?

The pH range for phenolphthalein is

Which salt is colourless?

Which salt is colourless?

Which ion is colourless:

Which of the following is colourless?

Which of the ion is colourless?

Which of the following is colourless gas

Two solutions A and B have pH values of 3.0 and 9.5 respectively. Which of these will turn litmus solution from blue to red and which will turn phenolphthalein from colourless to pink?