Chem 2 lab FINAL

scaryyy

When sodium hydroxide reacts with a weak acid, what will the spectator ion be?

Na⁺

The weaker an acid is, the _______ its K_a and the _____ its pK_a

smaller, larger

What ion is used in the Qualitative analysis lab part 1 to form insoluble chloride compounds?

Ag⁺ and Hg₂²⁺

Which ions are separated out as Group II metal hydroxides in the Qualitative analysis lab part 1 ?

Fe³⁺ and Mn²⁺

What are the hazards that needed to be kept under the hood for the part 1 qualitative analysis lab?

HCl, DMG, NH₃

What ion or ions can be detected by using potassium thiocyanate?

Fe³⁺

The substance added to unknown tube to separate silver and mercury in the qualitative analysis lab part 2 was 

HCl

The possibile ions that you can have Group B are

Mn²⁺ and Fe³⁺

A dark precipitate seen after adding 1M NaOH to solution B indicates which ions? (Qualitative analysis lab part 2)

Mn²⁺ and Fe³⁺

^{money fees are dark and scary}

Which of the following lead you to identify Hg₂²⁺ in your unknown

HCl and NH₃

Which ions will be in solution when identified?

Fe³⁺ and Cu<sup>2+

Felines see you</sup>

When electroplating Cu onto a coin, the mass of copper depends on what?

amount of current, number of electrons in the redox reaction, amount of time

In a concentration cell what is true? 

E^o cell does not equal E cell

What is true of Q under standard conditions?

Q=1

in a _____ cell, current is produced from a spontaneous chemical reaction

voltaic

Although the Colorimeter measures % transmittance, it is converted into ______ for the graph.

absorbance

After graphing your line, you will be given a correlation value.  This tells you how well the data fit the_____ .  A good value is greater than ____.

line

0.9

Beer's Law states the ______ relationship between concentration and absorbance.

direct

When placing the cuvette into the slot, be sure to have the ______ sides lined up with the arrow.

smooth

What is the meaning of ‘Ka’ in terms of physical significance? What is the equation that defines it?

Ka is the measurement of the strength of an acid in solution. 

the formula is 

What is the relationship between the concentration of the acid, hydronium ion, and anion in that equation?

For a storing acid, the hydronium ion concentration is equal to the inital acid concentration

for a weak acid the hydronium ion concentration is less than the initial acid concentration 

What is the pKA? how is it determined from the Ka?

The pka is a measure of a substance’s inherent tendancy to donate a proton. it is difference from the ka because it is the negative log of the acid disassociation constant (Ka)

How is the pH related to the pKa at the halfway point of a titration?

at the halfway point, the pKa of the acid is equal to the pH of the solution. 

What indicator was used in the titration lab?

phenolphthalein

What was the color of the solution before the endpoint in the titration lab?

clear (CHECK)

What was the color after the endpoint in the titration lab? 

light pink

fucking flow chart shit

What did a grey precipitate indicate?

Hg₂²⁺ (HgNH₂Cl)

What did a White precipitate indicate the presence of?

Ag⁺ (AgCl)

What did a blue solution indicate the presence of?

Cu²⁺ (Cu(NH₃)4²⁺

What did a pink precipitate indicate the presence of? What did you have to  add to get to it?

Ni²⁺ (Ni(DMG)2)

DMG

What did a Red solution indicate the presence of? What was added to get there? 

Fe³⁺ (Fe(CNS)6^3-)

KSCN

What did a purple solution indicate the presence of? What was added to get here? 

Mn²⁺ (MnO4⁺)
6M HNO2 and NaBiO3 were added to get to this 

Which were the only identified that were precipitates?

Gray (Hg2²⁺) and White Ag^{+ (chekc)}

what is the proper procedure for using a centrifuge?

balance the centrifuge with a tube of water on the exact opposite side of where you put the tube containing the solution, run it for about 30sec- 1 min 

What type of litmus paper would you use to test for acidity of a solution?

blue litmus paper 

What type of litmus paper would you use to test to see if a solution was basic?

red litmus paper

if a metal is being ______ it is attached to the anode

oxidized

if a metal is being ______ it is attached to the cathode

reduced

What is the equation for beer’s law? 

Beer's Law: A = (εl)c

What type of graph could be constructed using beer’s law? What would it look like? What would be plotted at each axis? Would data be linear?

you could construct a linear regression graph with beer’s law. It would look like a line going up 

A = εlc to y = mx + b.

For beer’s law, which variables from the equation would be the slope of the line? What would be the intercept and what should it be theoretically

A=y

Eb=m 

c=x 

y intercept= 0 

What are the reasons of making a standard curve for the beers law lab? What are the limitations? 

to ensure precision and accuracy of your measurements 

limitations: only valid for low concentrations and ideal conditions (?)

What are the formulas for how absorbance relates to % transmittance and how it relates to concentration?

A= 2-log(%T)

locate the pH on the graph 

A

locate the volume added on this graph

D

locate the half equiv point on this graph

B

locate the equiv point on this graph

C

What is NH₃

Ammonia

What is HgNH₃Cl

Ammoniated Mercury 

What is KNO₃

Potassium nitrate 

What is AgCl?

silver chloride

What is Cu(NH₃)₄²⁺

tetraamminecopper(II) ion

What is Ni(DMG)₂

dimethylglyocimate

What is NaOH

sodium hydroxide

What is KSCN

potassium thiocyanate 

What is Fe(CSN)₆³⁺

hexacyanoferrate (III)

What is MnO₄⁺

Permanganate 

Which reagent leads to the precipitation of group I cations as chlorides?

3M HCl

Which reagent dissolves some precipitates, forms compexes such as Cu²+

6M NH₃

Which reagent precipitates Ag⁺ as AgCl?

6M HNO₃

Which reagent precipitates group II sulfides?

H₂S (?)

Which reagent distinguishes Fe³⁺ and Mn²⁺

NaOH

Which reagent Identifies Fe³⁺

KSCN (red)

What reagent oxidzes Mn²⁺ to MnO₄^- 

HNO3 and NaBiO₃

_(purple)

What reagent identifies Ni²⁺

DMG (pink)

What is NaBiO₃

Sodium bismuthate

What reagenet led to the precipitation of Ag⁺

6M HNO₃