What is the charge of an atom with 21 protons and 20 electrons?

Explain the relationship between forward and backward reactions in equilibrium, and predict how changing the amount of a reactant (creating a tension) will affect that relationship.

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.

Calculate the percent composition by mass of each element in al(oh)3. use at least three significant figures.