When testing for hydrogen gas in the laboratory a glowing splint is inserted into the gas which results in a pop sound. What is associated with the formation of the pop sound? A. physical change
B. chemical change
C. exothermic reaction
D. endothermic reaction

Margaret wants to make an orange flavored drink by stirring powdered drink mix into a glass of water. she doesn't like drinks that have small clumps of powdered solid in them, so she wants the drink to be a perfect solution. what factors should margaret not consider when deciding how much powder to add to her glass of water?

What three natural resources are found in the great lakes region

Cucl2 + 2nano3 cu(no3)2 + 2nacl what is the percent yield of nacl if 31.0 g of cucl2 reacts with excess nano3 to produce 21.2 g of nacl? 49.7% 58.4% 63.6% 78.7%