Which of the following pairs of aqueous solutions will form a precipitate when mixed? Ca(C2H3O2)2 + Na2SO4 KOH + Na2S KNO3 + LiOH (NH4)2SO4 + KI None of the above solution pairs will produce a precipitate.

Particles vibrate in a rigid structure and do not move relative to their neighbors.

What rule is used to determine how many covalent bonds an element can form? a. the number of covalent bonds is equal to six c the number of covalent bonds is equal to five minus the group number plus the group number b. the number of covalent bonds is equal to eight d. none of the above minus the group number select the best answer from the choices provided

Wind and moving water provide energy. chemical mechanical thermal none of the above