Calculate the density of He gas at 1atm of pressure and 20.00C. Explain (using your calculated results) why Helium is used in modern day blimps.

A gas filled balloon having a volume of 2.50 L at 1.2 atm and 20⁰C  is allowed to rise to the stratosphere (about 30 km above the surface of Earth), where the temperature and pressure are -23⁰C  and 3.00 x 10 -3 atm, respectively. Calculate the final volume of the balloon

A sample of a gaseous binary compound of boron andchlorine weighing 2.842 g occupies 0.153 L at 0°C and1.00 atm pressure. This sample is decomposed to givesolid boron and gaseous chlorine (Cl2). The chlorine occupies 0.688 L at the same temperature and pressure. Determine the molecular formula of the compound.

7.  If 10.0 L of neon gas exerts a pressure of 25.0 atm at 50oC, how many moles of neon are present?

Which gas law does NOT have a directly proportional relationship between its properties? Boyle Charles Gay Lussac Avogadro

What volume (in L) does a 1.34 g  sample of chlorine gas occupy at SATP?

3. Under STP conditions what is the density of O₂ gas?

What mass of helium gas is needed to pressurize a 92.0 L tank to 209 atm at 18 °C? What mass of oxygen gas would be needed to pressurize a similar tank to the same specifications? Mass= g He Mass= g 0₂

9. What is the mass of the solid NH4Cl formed when 73.0 g of NH3(g) are mixed with an equal mass of gaseous HCl? What is the volume and identity of the gas remaining, measured at 14.0°C and 752 mmHg? NH3(g) + HCl(g) → NH4Cl

A 25.0 mL sample of neon gas at 395 mmHg is cooled from 105 ∘C to 15 ∘C. If the volume remains constant, what is the final pressure? Express your answer with the appropriate units.