Why is it difficult to collect evidence about the sky

What type of organic molecule comprises the majority of a potato?

The element chlorine has two stable isotopes, chlorine-35 with a mass of 34.97 amu and chlorine-37 with a mass of 36.95 amu. from the atomic weight of cl = 35.45 one can conclude that:

Twenty-seven milliliters of an acid with an unknown concentration are titrated with a base that has a concentration of 0.55 m. the indicator changed color when 12.5 milliliters of base were added. what is the concentration of the unknown acid?