It is not correct to say " a molecule of salt " because salt is a compound.
Explanation:
- As we know a molecular bond is present in each molecule.
- Salt (NaCl) is considered as a compound because it is made up of two types of elements that are sodium as well as chlorine.
- On the other hand it is not considered as a molecule as it is not holding an ionic bond.
- As a result we can name it as an ionic compound. Hence it is not considered as a molecule of salt.
Answer is: a) in the presence of a base.
Phenolphthalein is colorless in acidic solutions and pink in basic solutions.
Acid-base indicators are usually weak acids or bases and they are chemical detectors for hydrogen or hydronium cations.
Example for acid-base indicator is phenolphthalein (molecular formula C₂₀H₁₄O₄).
When solution turns phenolphthalein pink, it means it is basic (pH>7).
I would say because the respiratory system brings in the oxygen for the body and the circulatory system moves it throughout the body with the blood
Basic facts about sex and reproduction, as told to a child
