4 Select the correct answer.
Which statement best describes how chemical equations demonstrate conservation of mass?
O A.
The number of reactants is the same as the number of products.
O B.
The compounds are the same on each side of the reaction.
O c.
The number of atoms of each element is the same on each side of the equation.
OD.
The state of matter is the same on each side of the equation.

Which function is performed by earths atmosphere? a. ultraviolet rays are prevented from reaching the ozone layer. b. earths temperature is raised and moderated by trapping in heat c. charged particles from the sun are prevented from reaching earth. d. magnetic charges from space are prevented from reaching earths surface.

Neils bohr believed that electrons orbited the nucleus in different energy levels, based on strong support from

Achemistry student needs to standardize a fresh solution of sodium hydroxide. he carefully weighs out of oxalic acid , a diprotic acid that can be purchased inexpensively in high purity, and dissolves it in of distilled water. the student then titrates the oxalic acid solution with his sodium hydroxide solution. when the titration reaches the equivalence point, the student finds he has used of sodium hydroxide solution.calculate the molarity of the student's sodium hydroxide solution. be sure your answer has the correct number of significant digits.