Which of the following molecules is the least polar?
(a) ph₃
(b) ch₄
(c) h₂o
(d) no₂
(e) hcl

Melting and boiling are endothermic processes. this means that these processes absorb energy from their surroundings in order to occur. use this information and the data you collected in the phase change gizmo to describe what happens to the temperature of water when you boil it, then explain why this result occurs.

If a solution is considered basic, then a) the hydroxide ion and hydronium ion concentrations are equal. b) the hydroxide ion concentration is less than the hydronium ion concentration. c) the hydronium ion concentration is greater than the hydroxide ion concentration. d) the hydroxide ion concentration is greater than the hydronium ion concentration.

Chen drew a diagram to compare the ways in which different organisms obtain nitrogen. which label belongs to the area marked z?