What two reactants are necessary in order for a hydrocarbon combustion reaction to take place?

Which statement justifies that phosphine (ph3) is a polar molecule?

Which of these properties, used alone, would be least useful in identifying most minerals? a. color b. luster c. streak d. density

24. a sports ball is inflated to an internal pressure of 1.85 atm at room temperature (25 °c). if the ball is then played with outside where the temperature is 7.5 °c, what will be the new pressure of the ball? assume the ball does not change in volume nor does any air leak from the ball a) 0.555 atm b) 1.74 atm c) 1.85 atm d) 1.97 atm