Which reactions are endothermic? (select all that apply.) a. h2(g) + ½o2(g) h2o(aq), h = -57.83 kcal/mole b. ½ n2(g) + ½o2(g) no(g), h = +21.6 kcal/mole c. ½n2(g) + o2(g) + 8.1 kcal no2(g) d. ½n2(g) + 3/2 h2(g) nh3(g) + 11.0 kcal/mole e. nh3(g) ½n2(g) + 3/2 h2(g), h = +11.0 kcal/mole

Which statement best describes the liquid state of matter? a. it has definite shape but indefinite volume. b. it has definite shape and definite volume. c. it has indefinite shape and indefinite volume. d. it has indefinite shape but definite volume.

The size (radius) of an oxygen molecule is about 2.0 ×10−10m. make a rough estimate of the pressure at which the finite volume of the molecules should cause noticeable deviations from ideal-gas behavior at ordinary temperatures (t= 300k ). assume that deviatons would be noticeable when volume of the gas per molecule equals the volume of the molecule itself.

How to draw a diagram to represent a calcium metal lattice?