Chapter 6 Flashcards
Is water polar or nonpolar?
polar molecule
What is the shape of water?
bent
What can water do that makes it so unique?
it can dissolve more substances than any other liquid
What happens when salts dissolve in water?
a hydration shell forms around the ions of a salt
What is the hydration process?
interaction between water molecules and charged ions
How do you write the chemical equation for hydration?
H2O (l) ionic compound (s/l/g) ----> + ion (aq) + - ion (aq)
What is solubility?
amount of substance that can be dissolved in a solvent
What is a solute?
substance being dissolved
What is a solution?
substance doing the dissolving
What does the term “likes dissolves likes” mean?
non polar will dissolve with nonpolar and polar will dissolve with polar
What ion does water interact with?
hydroxide ions
why don’t oil and water mix?
oil is majority non-polar while water is polar
What part of oil can only interact with water?
the carboxyl group and the rest of the oil is a hydrocarbon chain that is nonpolar
What are aqueous solutions?
the substance is dissolved in liquid water
What is electrical conductivity?
the ability of a solution to conduct electricity
Does pure water conduct electricity?
no
What has to be added to water for it to conduct electricity?
ions and water together
What are electrolytes?
substances that produce a conductive solution when dissolved in water
What are strong electrolytes?
can completely ionic when dissolved in water
What kinds of bonds are typically found in strong electrolytes?
ionic and covalent
What are weak electrolytes?
partially dissociate/ionize in water
What is an example of a strong soluble salt?
NaCl
What is an example of a strong acid?
HCl
What is an example of a strong base?
NaOH
What is an example of a weak acid?
acetic acid
What is an example of a weak base?
ammonia
What are nonelectrolytes?
do not ionize when dissolved in water
What is an example of a nonelectrolyte?
ethanol (alchohol) and sucrose
What forms around nonelectrolytes?
a hydration shell
What is molarity?
the measure of concentration aka how many moles of a solute per liters of solution
What is the formula for molarity
M = moles of a solute / L of a solution
What are standard solutions?
have concentrations that are accurately known
What is dilution?
process of adding water to a concentrated solution
What are stock solutions?
concentrated solutions which are used to make less concentrated solutions
What is the dilution formula?
M1V1 = M2V2 (molarity before diffusion times the volume before dilution equals the molarity after the dilution times the volume after the dilution)
Does the amount of moles of solute change when diluting a stock solution?
NO
How do you determine if a compound is a strong, weak, or nonelectrolyte
is it strong acid or base? means it is a strong electrolyte
is the ionic compound completely soluble? it is a strong electrolyte
if the first two criteria are not fulfilled to a certain extent, then it is a nonelectrolyte
What is a precipitation reaction?
involves the formation of an insoluble substance when two solutions are mixed
The solid that is formed during a precipitation reaction is called a what?
precipitate
For a net ionic equation to happen, what has to be on the product’s side?
the insoluble product that forms a solid
What are spectator ions?
ions that don’t participate in the reaction
How do you write a net ionic equation?
Formula Equations (include chemical formulas and states)
Complete ionic equations (include all ionic species present)
Net ionic equations (remove spectator ions)
In the solution base stoichiometry problems, what do you have to consider when products are formed?
the limiting reagent! (convert moles of reactant to moles of product and compare)
What are acids?
H+ donors
What are bases?
H+ acceptors
In a net ionic equation involving bases, what should you consider?
OH making the water as a product
What are acid-base reactions also called?
neutralization reactions
What is titration?
adding a volume of known concentration
to the solution being analyzed
What are oxidation-reduction reactions also called?
redox reactions
What do redox reactions involve?
transfer of one or more electrons
What are oxidation states?
(or numbers) allow us to keep track of
electrons during reactions
An element alone has what oxidation state?
0
What is the oxidation state of a monoatomic ion?
the same as its charge (ex: NaCl is +1 -1)
What is the oxidation number for fluorine in COMPOUNDS always?
-1
What is the oxygen oxidation state in compounds?
-2
What is the oxidation state exception for oxygen?
-1 when talking about peroxide
What is the oxidation state for hydrogen in compounds?
+1
How do you know if a reaction is a redox reaction?
the oxidation numbers changed and the ions changed
What is oxidation?
loss of electrons
What is reduction?
gain of electrons
What are oxidizing agents?
electron accepters
What are reducing agents?
electron donors
What is conserved in a redox reaction?
matter and energy
How do you balance a redox reaction?
1) Write the unbalanced chemical equation (include states)
2) Determine oxidation states for all atoms
3) Show electrons gained/lost using “tie lines”
4) Use coefficients to equalize electrons gained/lost
5) Balance the rest of the equation using inspection
