Why does liquid bromine react slowly as compared to bromine vapor

What can be added to the examples section of each circle? endothermic: ice melting into water, and a heat pack becoming warm exothermic: a glow stick glowing, and fireworks exploding endothermic: ice melting into water, and an instant ice pack turning cold exothermic: fireworks exploding, and gasoline burning endothermic: a glow stick glowing, and a heat pack becoming warm exothermic: an instant ice pack turning cold, and ice melting into water endothermic: gasoline burning, and an instant ice pack turning cold exothermic: ice melting into water, and an instant ice pack turning cold

Explain which group an element with the electron configuration 1s2 2s2 2p6 3s2 3p6 3d1 4s2 belongs to.

Which statement is true regarding the diagram of circle p? the sum of y and z must be 2x. the sum of y and z must be x. the difference of z and y must be 2x. the difference of z and y must be x