Aflask has 20 L of methane inside at a pressure of 200kPa and a temperature of 300K. How many moles of methane are in the flask?
ROUND TO SIGNIFICANT FIGURES. (Hint: use the right R *

Asample of silver (with work function ? = 4.52 ev) is exposed to an ultraviolet light source (? = 200 nm), which results in the ejection of photoelectrons. what changes will be observed if: silver is replaced with copper (? = 5.10 ev) more photoelectrons ejected no photoelectrons are emitted fewer photoelectrons ejected more energetic photoelectrons (on average) less energetic photoelectrons (on average)

The volume of an unknown substance in a sealed glass jar is 50 milliliters. the volume of the jar is 200 milliliters. which state of matter could the substance be?

How many liters of oxygen gas, at standardtemperature and pressure, will react with 35.8 grams ofiron metal? 4 fe (s) + 3 o2 (g) → 2 fe2o3 (s)