Which of the following is a pure substance made up of one type of atom?
A) bronze
B) lead
C) steel
D) brass

Noble gases are the most reactive elements on the periodic table. a. true b. false

What is the molarity of 60.0 grams of naoh dissolved in 750 milliliters of water? a) 1.1 m b) 2.0 m c) 12 m d) 75 m

Answer asap : ( a. how does mucus prevent the entry of pathogens? b. describe two ways white blood cells protect us from pathogens.