4. a 5.4 kg basketball approaches sally with a velocity of 6.5 m/s. sally bumps the ball, giving it a speed
of 7.7 m/s but in the opposite direction. what average force did she apply if the interaction time
between her hands and the ball was 0.15 seconds?

Nitric acid can be formed in two steps from the atmospheric gases nitrogen and oxygen, plus hydrogen prepared by reforming natural gas. in the first step, nitrogen and hydrogen react to form ammonia: (g) (g) (g) in the second step, ammonia and oxygen react to form nitric acid and water: (g) (g) (g) (g) calculate the net change in enthalpy for the formation of one mole of nitric acid from nitrogen, hydrogen and oxygen from these reactions. round your answer to the nearest .