You have a solution of NaOH with a concentration of 5.0M. You take 250.0 mL of the 5.0M solution and and add water until you have 500.0 mL of diluted solution. What is the concentration of the diluted solution to two significant figures?

Modern pennies are composed of zinc coated with copper. a student determines the mass of a penny to be 2.482 g and then makes several scratches in the copper coaling (to expose the underlying zinc). the student puts the scratched penny in hydrochloric acid, where the following reaction occurs between the zinc and the hcl (the copper remains undissolved): zn(s) + 2 hcl(aq) → h2(g) + zncl(aq)the student collects the hydrogen produced over water at 25 °c. the collected gas occupies a volume of 0.899 l at a total pressure of 79 j mmhg. calculate the percent zinc (by mass) in the penny. (assume that all the zn in the penny dissolves.)

Clyde and marilyn are riding a roller coaster. during which section(s) of the track is their potential energy converted to kinetic energy? a. from point b to point c only b. from point b to point d only c. from point a to point b only d. from point a to point b and from point c to point d

Idont understand it 1.what is the boiling point of a solution of 675 grams of ethylene glycol (c2h6o2) in 2.50 liters of water?