PLEASE PLEASE PLEASE HELP - 20 POINTS How many moles are there in 5.7 x 10^25 molecules of Na2SO4?*

Different isotopes indicate that an element will have different numbers of

Explain that newton first law, second law and third law of motion?

Which statement is true about hcl? (5 points) select one: a. it is a salt because it increases the concentration of metallic ions. b. it is a salt because it is formed by the reaction of an acid and a base. c. it is an acid because it increases the concentration of hydroxyl ions. d. it is an acid because it increases the concentration of hydronium ions.