General Chemistry II Test 1

polar solute/ polar solvent

polar solute/ polar solvent

dipole-dipole; it WILL dissolve

nonpolar solute/ nonpolar solvent

london disperson interactions; hydrophobic; it WILL dissolve

polar solute/ nonpolar solvent

almost no interaction - dipole induced dipole; london disperson; it WILL NOT dissolve

nonpolar solute/ polar solvent

amost no reaction; it WILL NOT dissolve

increasing the pressure of a gas over a liquid solvent

induced dipole (depending on the gas); the gas WILL better

increasing the temperature of a dissolving solid

it WILL dissolve better for majority of cases

increasing the temperature of a dissolving gas

increase the energy of a gas

endothermic

requires heat

exothermic

release heat

mass percent

solute mass/total solution mass * 100%

mole fraction

moles of solute/total moles

molarity (M)

moles of solute/ total volume of solution (L)

molality (m)

moles of solute/volume of solvent (kg)

vapor pressure

reduces vapor pressure

boiling point

should increase boiling point

freezing point

should decrease freezing point

osmotic pressure

increases osmotic pressure

which of the following salts is less likely to become less soluble in water as temperature increases?

Lithium sulfate (Li2SO4) - exception

which of these statements is true for a solution at saturation?

the rate of dissolution is equal to the rate of precipitation

what is the primary reason that sugar dissolves well in water?

hydrogen bonding - dipole-dipole interactions

how does the presence of a non-viable solute typically affect the boiling point of a solvent?

increases the boiling point

freezing point

decreases

boiling point

increases

in a zero-order reaction, how does the rate of reaction change with an increase in the concentration of the reactant?

remains constant

what is the term used to describe a sequence of reactions that depict what is happening to reactants?

reaction mechanism

the point in the reaction at which the reconstruction of existing bonds occurs is called:

transition state - movement of change in chemical reaction

if you dissolve 0.0856 moles of NaCl in enough water to make 500 mL of solution, what is the molarity of the solution>

0.171 M

0.0856 moles/0.5L = 0.1712 M

a solution causes a boiling pint elevation of 1.04ºC. if the molal boiling point elevation constatnt (Kb) is 0.52ºC/m and th solution’s molality is 3 m, what is the Van’t Hoff factor (i)?

1

change in Tb/Kb Cm = 1.04/0.052×2 = 1

if the concentration of a reactant decreases of 0.8 M of 0.6 M in 2 hours, what is the average rate of the reaction?

0.1 M/h

change of C/ change of t = 0.8-0.6 M/ 2 hours

=0.2/2

= 0.1 M/h

if tripling of concentration of a reactant leads to an increase of the initial rate by a factor of 27, what is the order of the reaction respect to that reactant?

k*C^n

27=3^n

n=3 - 3rd order reaction

the plot of ln(k) vs 1/T, can be described as ln(k) = 28.5 - (2.1×10^4)/T. what is the value of ln(A)?

k=A*e^-Ea/RT

ln(k) = lnA - Ea/R * 1/T (kelvin)

percent by volume

volume solute/total volume *100%

density

mass/volume

change of Tb

elevation of boiling point

Kb

molal boiling point elevation constatn

Cm

molality of the solution = moles solute/ kg of solvent

change of Tf

depression of the freezing point

Kf

molal freezing point depression constant

π

osmotic pressure

R

ideal gas constant = 0.08206 L atm/mol K

T

temperature in Kelvin

RT

a measure of the average translational energy of a collection of molecules

M

molarity of the solution

i

Van’t Hoff factor, which is the ratio of the moles of particles in the solution to the moles of solute dissolved

boiling point elevated

change of Tb = iKbcm

freezing point is depressed

change of Tf = iKfcm

osmotic pressure formula

π=iMRT

slope intercept

y=mx+b