What is the energy efficiency of a light bulb that gives you 30 units of usable energy for every 100 units of energy put in to it?
a. 0.3
b. 3
c. 30

What is the molecular formula for a compound that is 46.16% carbon, 5.16% hydrogen, and 48.68% fluorine? the molar mass of the compound is 156.12 g/mol

How many grams of oxygen gas are contained in a 15 l sample at 1.02 atm and 28°c? show your work.

Which of the following is most likely true about water in chemical systems? a) water dissolves nonpolar ionic compounds. b) water dissociates ionic compounds. c) water dissociates covalent molecules. d) water dissolves nonpolar covalent substances.