CHM 152 Buffers Jeopardy

What's the term?

100

_____: A measure of [H+] in a solution

pH

200

This equation involves the pH, the pKa, and also the log of the Base over the Acid

Henderson-Hasselbach Equation

300

The _____ of Base:Acid that has a pH=pKa, is equal to 1.

ratio

400

_______: A solution with ability to resist pH change (when small amount of strong acid or base are added)

Buffer

500

_____: a measure of acid strenth

pKa

Is it a buffer?

100

HCl/LiCl

HF/LiF

HCl/LiCl= No

HF/LiF=Yes

200

H₂CO₃/NaCO₃

(CH₃)₃N/CH₃COOH

H₂CO₃/NaCO₃= No

(CH₃)₃N/CH₃COOH= No

300

HCN/NaCN

(CH₃)₃N/(CH₃)₃NH⁺Cl-

HCN/NaCN=Yes

(CH₃)₃N/(CH₃)₃NH⁺Cl-=Yes

400

NaOH/H₂O

RbOH/H₂O

NaOH/H₂O=No

RbOH/H₂O=No

500

CH₃CH₂NH₂/CH₃CH₂NH₃Br

NH₃/NH₄Cl

CH₃CH₂NH₂/CH₃CH₂NH₃Br= Yes

NH₃/NH₄Cl= Yes

What is the compound?

100

HF

HNO₃

RbOH

Ca(OH)₂

Weak acid

Strong acid

Strong base

Weak base

200

HClO₃

HClO₄

CsOH

NH₃

HClO₃=Weak Acid

HClO₄=Strong Acid

CsOH=Strong Base

NH₃=Weak base

300

RbCl

HI

H₂SO₄

KOH

RbCl=Neutral salt

HI=Strong acid

H₂SO₄=Strong acid

KOH=Strong base

400

Ba(OH)₂

H₂CO₃

RbBr

RbF

Ba(OH)₂=Strong acid

H₂CO₃=Weak acid

RbBr=Neutral salt

RbF=Basic Salt

500

(CH₃)₂NH₂⁺Br^-

NaF

NaCH₃COO

NH₄Br

(CH₃)₂NH₂⁺Br^-=Acidic salt

NaF=Basic salt

NaCH₃COO=Basic salt

NH₄Br=Acidic salt

Old Stuff

100

What are the letters associated with enthalpy, entropy, and spontaneity

Enthalpy= H

Entropy= S

Spontaneity=G

200

A positive delta S indicates a(n) ______ in entropy

increase

300

Is the process of water freezing spontaneous? In what conditions?

Yes, but only at low temperatures

400

Make the appropriate balanced combustion equation that starts with 4 moles of CH₄

4CH₄  +  8 O₂   ---->  8H₂O   +   4CO₂

500

Rey is making Mac and Cheese in his small dorm room kitchen. He starts boiling the water to put the pasta in. What are the signs of delta H, delta S, and delta G for the boiling water?

H=+

S=+

G=-

Calculations

100

Calculate the pH of a buffer solution with 0.48 M NaCN and 0.89 M HCN at 25 degrees Celsius.

Ka= 3.9 E -4

pH=3.14

200

Calculate the pH of a buffer solution with 0.78 M LiF and 0.98 M HF at 25 degrees Celsius.

Kb=4.7 E -5

pH= 9.57

300

What is the pH of a solution of HCl with a concentration of 0.72 M?

0.14

400

Calculate the pH of a buffer solution with 0.57 NH₃ and 0.85 NH₄Cl at 25 degrees Celsius. 

Ka= 1.57 E -5

Calculate the pH after adding 0.1 mol LiOH. Assume no change in volume. Then, calculate the change in pH. Assume 1.0 L of solution and use the same Ka. (you need 3 answers)

Initial pH=4.63

pH after the strong base is added=4.76

Change in pH= ~.13

500

A is third order and B is second order.

An experiment is run with 0.24 M of A, 0.67M of B, and has an initial rate of 16.7 M/s. What's the value of the rate constant?

2700 M/s