True or false: A nebula is a region of gas and dust where stars are born, whereas a planetary nebula occurs at the end of a stars life and is the remains of an average star after it becomes a red giant

In the analysis of hair and fiber samples, which does a compound comparison microscope allow for that a conventional compound microscope does not? a. simultaneous observation b. polarization c. fluorescence d. higher magnification

If 34.2 grams of lithium react with excess water, how many liters of hydrogen gas can be produced at 299 kelvin and 1.21 atmospheres? 2 li (s) + 2 h2o (l) yields 2 lioh (aq) + h2 (g)

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