Chemistry Mid-term Review. Ch. 10, 11,13,14, and 15. Material You Should Review. From Last Year! Sig figs Types of Mixtures Exothermic vs. Endothermic Theories of the Structure of the Atom Emission Spectrum Orbitals Trends of the Periodic Table Valence electrons
Chemistry Mid-term Review
Ch. 10, 11,13,14, and 15
From Last Year!
From This Year!
Crystalline solids have a crystal lattice with repeating 3D patterns.
Amorphous have no lattice and random order
Pressure of gas molecules all objects in the Earth’s atmosphere experience. 1 atm = 760mmHg= 14.7 psi= 101.3 kPa
Kelvin directly relates the motion of the particles which produces the pressure of the gas.
Pressure produced by a vapor as a liquid changes to a gas. When vapor pressure and atmospheric pressure are equal, a liquid will boil.
Heat of fusion- amount of every needed to melt 1kg of substance
Heat of evaporation- amount of energy needed to vaporize 1kg of substance
V1P1=V2P2; Volume and Pressure are inversely proportionate
V1/T1=V2/T2; Volume and Temperature are directly proportionate
P1/T1=P2/T2; Pressure and Temperature are directly proportionate
PV=nRT; connection between molar concentration of an ideal gas and its V, P, and T.
V1/n1=V2/n2; Moles of gas and the volume of the gas are directly proportionate
Ptotal=P1+P2+P3+…; total pressure is equal to sum of all none reactive gases
V2 = V1T2/T1= (10.0L x 423K)/298K = 14.2L
V2 = P1V1/P2 = (0.66atm x 3.0L)/5.0 atm = 0.40 L
P2=P1T2/T1=(475.0 mmHg x 358K)/312K =546 mmHg
V2= P1V1T2/P2T1= (1.77 atm x 2.00L x 324K)/(4.01 atm x 303K)
n=(75 atm)(14.0L)/(0.08206 L atm/ mol K)(295K)
n= 43 mol of NO2
At 4oC the water molecules are their most dense but as the temperature lowers the H-bonds form hexagonal shapes which forces water to expand as it freezes. This results in ice be less dense than water.
Adhesion- water molecules sticking to surfaces
Cohesion- water molecules sticking to each other
Capillary action- water moving up tubes against gravity
Surface tension- water molecule resistant force on its surface
High specific heat- water can absorb a lot of energy and releases it slowly
Unsaturated- still able to dissolve solute in the solvent
Saturated- maximum amount of solute within the solvent
Supersaturated- raising the temperature allows for extra amounts of solute to dissolve in the solvent; crystalizes when cooled
M= 0.6784 molNaCl/ 4.5 L H2O
M= 0.15 mol/L = 0.15 M
977.6 mL H2O
1 L H2O
119.0 g KBr
= 349 g KBr
1000 mL H2O
1 L H2O
Solution- solute completely dissolved; light pass through
Colloid- solute completely dissolved; light scatters
Suspension- solute separates over time; often reflects light
Light photons passing through a colloid collide with particles in the solution and scatter in random directions causing the colloid to glow
Using the “Like dissolves Like” rule, a non-polar molecules dissolve into non-polar substances and polar molecules dissolve into polar substances
Solutes dissolved in the solvent take up space between the solvent molecules. When the solution is boiling, the solute particles take up space on the surface of the solution which lowers the vapor pressure, so more energy (higher temp) is needed to boil the solution. When freezing the solutes take up space between the solvent molecules and prevent them from moving close together, so more energy (lower temp) must be removed to freeze the solution
A solution containing dissolved ions which will allow the passing of electrons through the medium. The more ions present the easier it is for the electricity to pass through the solution.
Breaking a covalent compound into ions. Happens with acids dissociating in solution
Acids produce hydronium ions (H+) in water while bases produce hydroxide ions (OH-) in water.
B-L definition Acids give off H+ while bases take H+
SO3 (non-metal oxide) when mixed with water produces an acid (H2SO4) so it is an acidic anhydride
ZnO (metal oxide) when mixed with water produces a base (ZnOH) so it is a basic anhydride
Strong acids/bases dissociate completely in solution but weak acids/bases only dissociate a little
pH + pOH = 14
pH indicators are used to monitor pH changes Litmus paper can tell you if you have an acid or a base and liquid indicators that work in certain pH ranges will tell more specifically what your pH might be.
[OH-] = 10-10 = 1.0x10-10 M
pH = -log[1.0 x10-4] = 4
pOH= 14- 5= 9; [OH-] = 10-9= 1.0x 10-9 M
0.0001 M NaOH = 0.0001 [OH-]
pOH= -log [0.0001] = 4
pH= 14-4 = 10
Acid + Base A Salt + H2O
HCl + NaOHNaCl + H2O
KOH + HCl KCl + H2O
OH- + H+ H2O
Strong Base+ Weak Acid
Weak aciddoesn’t dissociated enough to neutralize all the OH -ions produced by the base
A solution of a weak acid or base and the salt of that same weak acid or base. Solution has compounds that will react with additional H+ and OH- ions so the pH of the solution changes slowly over time
An acid‐base titration requires 29.88 mL of 1.17MNaOH to
neutralize5.00 mL of an H2SO4 solution. Calculate the molarity of theH2SO4 solution.
2 NaOH (aq) + H2SO4 (aq) Na2SO4 (aq) + 2 H2O (l)
MA= (29.88ml)(1.17M)/(2)(5.00ml)= 3.50 M H2SO4
A 20.00‐mL sample of oxalic acid, H2C2O4, solution is titrated with
27.86 mL of 0.250 M KOH solution. Calculate the molarity of the
2 KOH (aq) + H2C2O4 (aq) K2C2O4 (aq) + 2 H2O (l)
MA= (27.86ml)(0.250M)/(2)(20.00ml)= 0.174 M H2C2O4