Circle the letter of the best answer.
1. Which statement is true?
a. Mole ratios limit the number of significant figures in a calculation.
b. You must know the masses of all the reactants in a chemical equation in order to determine the
masses of all the products.
c. The mole ratio is needed only to solve problems in which the given is a mass in grams and the
unknown is an amount in moles.
d. A mole ratio can only be determined from a correctly balanced chemical equation.

Which explanation is true about what happens to a ray of light when it strikes a mirror? a. a light ray is transmitted toward a mirror at a certain angle. the light ray is then reflected by the mirror at an equal angle but in the opposite direction of the transmitted ray. b. an incident ray strikes a mirror at an angle with a line perpendicular to the mirror. the light ray is then reflected at an angle equal to the angle of incidence but on the opposite side of the perpendicular line. c. a reflecting ray strikes a mirror at an angle with a line perpendicular to the mirror. the light ray is then refracted at an angle equal to the angle of the reflecting ray and on the same side of the perpendicular line. d. an incident ray strikes a mirror at an angle with a line parallel to the mirror. the light ray is then transmitted at an angle equal to the angle of incidence but on the opposite side of the parallel line. you so much! : -d take the time to try and answer correctly.