How many significant figures are in the number 50.5

Identify the balanced chemical equation that represents a decomposition reaction. p4 + 3o2 ⟶ p2o3 2fe(oh)3 ⟶ 2feo3 + h2o cuso4 ⟶ cuo + 2so3 2fe(oh)3 ⟶ fe2o3 + 3h2o

Which function is performed by earths atmosphere? a. ultraviolet rays are prevented from reaching the ozone layer. b. earths temperature is raised and moderated by trapping in heat c. charged particles from the sun are prevented from reaching earth. d. magnetic charges from space are prevented from reaching earths surface.

This is a characteristic of the elements in the periodic table that shows a pattern. it may increase or decrease across or down the table.