You are holding two balloons of the same volume at STP. One balloon contains 1.0 g of helium. The other balloon contains neon. What is the mass of neon in the balloon?

What is the density in g/L of Chlorine gas at STP (remember chlorine is diatomic)?

What is the mass (in g) of 258 mL of sulfur trioxide measured at STP?

If 12.4L of sulfur trioxide, SO3, decomposes into sulfur dioxide, SO, and oxygen, what volume of oxygen is produced at STP? SO,→ SO2 + O2

2.00 liter of nitrogen at 26.35 torr is mixed with 2.00 liter of helium at 42.45 torr and a third gas, oxygen. Together, the three gases exert a pressure of 1,245.32 torr in a 2.00 liter container. What is the pressure of the oxygen gas in torr? (Answer to two decimal places and no units in your answer please.)

Consider the formation of nitrogen dioxide from nitric oxide and oxygen: 2 NO(g) + O2(g) → 2 NO2(g) If 6.79 L of NO is combined with excess O2 at STP, what is the volume in liters of the NO2 produced?

What is the mass (in g) of 339 mL of sulfur trioxide measured at STP?

A gas sample at STP contains 4.28 g of ammonia gas, NH3. What is the volume of the ammonia gas?

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An analyst knows that a sample of gas is either carbon dioxide or carbon monoxide. The analyst determines that 250mL of the gas has a mass of 0.31g. Is the gas carbon dioxide or carbon monoxide? Assume the test was done at STP. Explain!