The standard heat of formation of nabr is -360.0 kj mol-1. the energy needed to vaporize one mole of br2(l) to give br2(g) is 31 kj mol-1. energy needed to vaporize one mole of na(s) is 107.8 kj. the first ionization energy of na is 495.4 kj mol-1. the bond energy of br2 is 192 kj per mole of br—br bonds. the lattice energy of nabr is -743.3 kj mol-1.

Aprojectile is launched from ground level with an initial velocity of v 0 feet per second. neglecting air resistance, its height in feet t seconds after launch is given by s equals negative 16 t squared plus v 0 t. find the time(s) that the projectile will (a) reach a height of 192 ft and (b) return to the ground when v 0equals112 feet per second. (a) find the time(s) that the projectile will reach a height of 192 ft when v 0equals112 feet per second. select the correct choice below and, if necessary, fill in the answer box to complete your choice.