Which of the following pairs of items will be attracted by one another?

a. a positively charged pith ball and a negatively charged glass rod
b. two positively charged pith balls
c. a negatively charged pith ball and a negatively charged glass rod
d. two negatively charged pith balls

Which of the following is always a reactant in a combustion reaction? oxygen nitrogen hydrogen carbon

Silver tarnishes as silver metal reacts with hydrogen sulfide, h2s, in the air. in this reaction, dark silver sulfide, au2s, covers the surface of silver. when silver is polished, this coating of silver sulfide can be removed from the surface. this makes the silver shiny again. enter the coefficients that balance the tarnishing reaction equation. (type 1 for no coefficient.)

Which type of precipitation would most likely form when the surface air temperature is slightly below freezing and the air temperature increases as you move upward away from the ground?