DAT Chem ch 7

Question 1

solubility rule 1 (most of the ionic compounds that have any of the following are soluble in water

Answer 1

nitrate NO3- perchlorate ClO4- Acetate C2H3O2- Ammonium NH4+ and group 1 metal cations

Question 2

solubility rule 2 ( most ionic compounds that have any of the following are insoluble in water water

Answer 2

Ag+ Pb2+ S2- OH- Hg22+ Po43-

Question 3

when a ionic compounds has as insoluble and soluble element which wins?

Answer 3

the soluble

Question 4

Net ionic equation Steps (summary

Answer 4

1) balance
2) use the solubility rule to label everything
3) cut all the aq in half separating their cation and anion (do not touch the insoluble) it cannot be separated
4) Cancel out all the species that are the same (these are the spectator ions)

Question 5

Formula for solutions (concentrations)

Answer 5

molality = moles solute/kg of solvent
molarity = moles of solute/ L of solution

Question 6

as temp ____ the gas solubility ____

Answer 6

increase

decreases

Question 7

as temp ____ the solids solubility _____

Answer 7

increases

increases

Question 8

As pressure _____ the gas solubility ____

Answer 8

INCREASE

increases

Question 9

Henry’s law

Answer 9

Pa=Kh[A}
Pa is the gas pressure in the solution
[A] is the gas concentration in moles per liter (molarity)
Kh is the constant that differs for each gas, solvent, and temp

Question 10

What is colligative properties

Answer 10

properties of a solution that change as you add more solute

Question 11

solute ____ = _____ freezing point

Answer 11

increase
decrease
Why?
the more solute you add in water, the harder it is for the water molecules to link together to become solid. so temp must increase even more for it to freeze

Question 12

Solute _____ = _____ boiling point

Answer 12

increase
increase
Solute becomes a more organized state (lower entropy) when water evaporates due to high boiling point. It does not want a low entropy and is going to try to avoid being evaporated. causing the boiling point to increase to take it longer to evaporate

Question 13

How to calculate freezing point?

Answer 13

just count the molecules
bigger numebr wins
Ex/ 
NaCl = 2 
Na2So4 = 3
So Na2so4 wins

Question 14

Raoults law

Answer 14

Pa= XaPpure
Ppure= vapor pressure of the original solvent, when its pure
Xa= percentage of solvent in the new solution
Pa = solutions new vapor pressure

Question 15

When to use raoults law

Answer 15

what amount a solution’s vapor pressure decrease, when a solute is added?

Question 16

osmotic pressure formula

Answer 16

Pie= i MRT
Pie= osmotic pressure
i= vant hoff factor(how many things your molecules splits into
R= 0.0821
T= kelvin

Question 17

zero order reactions

Answer 17

plot is a straight line

decreased half life = decreased concentrations

Question 18

first order reactions

Answer 18

not a straight line
half life is constant
and is independent of concentration

Question 19

second order reactions

Answer 19

not a straight line

increased half life = decreased concentrations

Question 20

Collision theory

Answer 20

both molecules must collide
both must collide with enough energy
both must collide in the correct 3d orientation

Question 21

unsaturated

Answer 21

everything is dissolved

Question 22

saturated

Answer 22

not everything is dissolved