Which best describes how johannes kepler developed his laws of planetary motion

Consider the reaction: 2al(s) + fe2o3(s) → al2o3(s) + 2fe(s) the δhf for fe2o3(s) = -824.3 kj/mole. the δhf for al2o3(s) = -1675.7 kj/mole. finish the equation. δhrxn = [(1)( kj/mole) + (2)( kj/mole)] - [(1)( kj/mole) + (2) ( kj/mole)]

How many atoms are in 2 moles of phosphorus?

Robert leaves a chocolate bar in his car while attending school all day. when he goes to his car in the afternoon, the bat has changed into gooey liquid. what happened to the chocolate bar