How many mol of potassium are represented by 7.85 x 10^23 potassium atoms?

Which of the following is NOT an assumption about an ideal gas? a. There are no intermolecular forces of attraction. b. The molecules do not collide with each other. c. The molecules have no kinetic energy. d. The molecules occupy no volume.

During electrolysis, electrons flow from A) an anode to a cathode. B) a cathode to an anode. C) an electrolyte solution to a nonelectrolyte solution. D) a nonelectrolyte solution to an electrolyte solution.

While in Europe, if you drive 123 km per day, how much money would you spend on gas in one week if gas costs 1.10 euros per liter and your car's gas mileage is 24.0 mi/gal? Assume that 1euro=1.26dollars. Express your answer numerically in dollars.

A student is testing water to know which is best for cleansing purposes with soaps. He would find that the cleansing action of soaps is best when he uses water obtained from A. Rain B. Tap C. Hand pump D. Pond

If a chemist wants to make 1.3 L of 0.25 M solution of KOH by diluting a stock solution of 0.675 M KOH, how many milliliters of the stock solution would the chemist need to use?

How much energy is needed to convert 57.3 grams of ice at 0.00°c to water at 75.0°c? specific heat (ice) = 2.10 j/g°c specific heat (water) = 4.18 j/g°c heat of fusion = 333 j/g heat of vaporization = 2258 j/g?

A certain first-order reaction (A→productsA→products) has a rate constant of 9.90*10-3 s-1s-1 at 45 ∘C∘C. How many minutes does it take for the concentration of the reactant, [A][A], to drop to 6.

Assign the oxidation number for (NH4) 3PO4

When gold is melted and formed in a mold to make a piece of jewelry, what type of change is taking place?

Do pure substances have the same chemical and physical properties