The condensation reaction that forms nucleic acid polymers occurs between a group on one nucleotide and a group on a second nucleotide. a. phosphate, hydroxyl b. carbon, carbonc. nitrogenous base, sugar d. nitrogenous base, nitrogenous base

Awhite powder is added to a solution. the images show observations made before the powder is added, just after the powder has been added, and a little while later. (the liquid in the small beaker is phenol red solution.) what evidence shows that a chemical change has taken place?

Two changes are described below. a green banana turns yellow and ripens. a layer of rust forms on an iron nail. which statement is true about the two changes? a) both are chemical changes because new substances are formed. b) both are physical changes because only the physical state of the substances change. c) a is a physical change due to a change of state, but b is a chemical change because new molecules are formed. d) a is a chemical change due to a change of state, but b is a physical change because new molecules are formed.

Which is an example of a mixture? a. water b. trail mix c. hydrogen d.carbon dioxide