While looking out the window, you see lightening flash and then 3 seconds later, you hear the thunder. how far was the lightening from you?

a. 3,300 ft

b. 3 miles

c. 300 ft

If 1.8 l of water is added to 2.5l of a 7.0 molarity koh solution, what is the molarity of the new solution

Consider the reduction reactions and their equilibrium constants. cu+(aq)+e−↽−−⇀cu(s)pb2+(aq)+2e−↽−−⇀ pb(s)fe3+(aq)+3e−↽−−⇀fe(=6.2×108=4. 0×10−5=9.3×10−3 cu + ( aq ) + e − ↽ − − ⇀ cu ( s ) k =6.2× 10 8 pb 2 + ( aq ) +2 e − ↽ − − ⇀ pb ( s ) k =4.0× 10 − 5 fe 3 + ( aq ) +3 e − ↽ − − ⇀ fe ( s ) k =9.3× 10 − 3 arrange these ions from strongest to weakest oxidizing agent.

How many atoms or molecules are there in a mole of a substance?