Chem Get Gases MC Practice WS stamped off if you did not do so last class. Unit 5 Test Mon 1/29, Tues 1/30 Gas Laws Project due: Fri 2/2

Add to Cover Sheet Avogadro’s Law 1 mole of gas at STP = 22.4 L

Avogadro’s Law Equal volumes of gases at the same pressure and temperature contain the same # of molecules

Avogadro’s Law Ratio of # molecules = #moles = volume 2 molec 1 molec 2H2 + O2  2H2O

Avogadro’s Law Direct relationship increases As volume increase the number of moles _____________.

Molar Volume The volume of one mole of a substance 1 mole of any gas at STP is 22.4L If you have one mole each of O2 and H2, they will have the ______________ volume and __________ masses. same different

𝒙 𝟐𝟐.𝟒 𝑳 𝟏 𝒎𝒐𝒍𝒆 0.0680 mol = 1.52 L 𝟐𝟐.𝟒 𝑳 𝟏 𝒎𝒐𝒍 7.08 mol =159 L

Ideal Gas Law Describes the state of a hypothetical ideal gas. Good approximation of the behavior of many gases under many conditions.

PV=nRT Ideal Gas Law n= # moles R=universal gas constant Will be GIVEN on tests/quizzes! R is the universal gas constant. To determine which R to use in your equation you have to look at the _____________. Pressure units being used!!

n=2.30 mol PV = nRT T=45 + 273 =318 K 3.4 x V = 2.30 x 0.0821 x 318 V= 17.66 L P=3.4 atm R = 0.0821 V=?

Ideal Gas Law Examples 1) 17.66 L 2) 1984 K

0.0862 moles 0.0862 mol 𝒙 𝟒.𝟎𝟎 𝒈 𝟏 𝒎𝒐𝒍𝒆

= = = = 𝟓.𝟏𝟔 𝒈 𝟎.𝟎𝟑𝟗 𝒎𝒐𝒍𝒆𝒔

Gas Stoichiometry 1 2 1 2

3.5 L H2 𝟏 𝑳 𝑵 𝟐 𝟑 𝑳 𝑯 𝟐 =1.17 L N2

22.4 𝟏 𝒎𝒐𝒍𝒆 𝟐𝟐.𝟒 𝑳 𝟐𝟐.𝟒 𝑳 𝟏 𝒎𝒐𝒍𝒆 𝟏 𝒎𝒐𝒍 𝑵 𝟐 𝟑 𝒎𝒐𝒍 𝑯 𝟐 0.100 mol H2 𝟐𝟐.𝟒 𝑳 𝑵 𝟐 𝟏 𝒎𝒐𝒍 𝑵 𝟐 =0.747 L N2