What is the mass of 35.0L of oxygen?

Which of the following is not true about the atomic model of substances?

Two solids are mixed in a flask and stirred. after a few minutes, the flask becomes cold. which of the following best describes this reaction? a. an exothermic reaction b. a combustion reaction c. an endothermic reaction d. a decomposition reaction

Bridget is in science class. her teacher gives her two unknown substances and asks her to determine their relative ph. she places a piece of red litmus paper into both substances. the litmus paper turns purple when she places it into substance i. the litmus paper turns blue when she places it into substance ii. a. substance i is a neutral substance and substance ii is an acid. b. substance i is a neutral substance and substance ii is a base. c. substance i is an acid and substance ii is a base. d. substance i is a base and substance ii is a neutral substance.