Chemistry - November 2006

So I have to find the concentration of lead in seawater. I prepared a 50 mL sample of seawater containing 0.1 M KCl, 50 mM HNO3 and 30 ppm HG2+. I took 15 ml of the above sample and spiked the sample with 1 ppm Pb2+ and Cd2+ to get a final concentration of 0.01 ppm Pb2+ and Cd2+. Then i spiked the sample again with the 1ppm Pb2+ and Cd2+ to make 0.025 ppm Pb2+ and Cd2+. I continued to spike the sample until I go 0.05, 0.075, and 0.1 ppm Pb2+ and Cd2+. For lead my results were:

0 ppm = -719 mV
0.05 ppm = -708 mV
0.075 ppm = -702 mV
0.1 ppm = -698 mv

The above is for the seawater sample. My standards are below:

0.05 ppm = -719 mV
0.1 ppm = -718 mV
0.5 ppm = -708 mV

Can someone please show me how to get this concentration?

2006-11-03 01:30:41 · 1 answers · asked by Anonymous

2006-11-02 23:27:24 · 2 answers · asked by Darka 1

i have a periodic table but i can't figure out how to find the protons, nuetrons, and electrons. for helium, all it says in the right hand corner is 2. plz help. thanks and God bless you!!!

2006-11-02 23:26:22 · 8 answers · asked by Lacy L 2

2006-11-02 21:49:18 · 4 answers · asked by Dave 4

do i breath all of the oxygen out of the air with windows closed. i light my lighter when i first come in but hours later i cant light my lighter until i open a window

2006-11-02 21:37:16 · 10 answers · asked by r any 1

I've been searching for research articles for about a week and i can't find anything..
Even just a little info about ammonia excretion and bivalves would be really helpful! useful url's are also welcome!

2006-11-02 20:51:13 · 1 answers · asked by Sofia 1

2006-11-02 20:29:00 · 8 answers · asked by Anonymous

how to made pure C.
becauser in this world, carbon usually exist in CaCO3

2006-11-02 20:13:56 · 5 answers · asked by la montée 4

CuSO4
KNO2
Mg[OH]2
CH3COONa
Fe[OH]2
Fe[OH]3
Na2SO4
CaSO4
FeSO4
AgNO3
FeSO4
MgCl2
PCl5
HI
KI
NaI
NaF
AlCl3
MgCO3
HCN
KSCN
Fe2O3
KMnO4
KCr2O7
Cr(OH)3
FeS
K2SO4
Li2SO4
LiOH
NiSO4
AgCl
HBr

2006-11-02 19:27:30 · 2 answers · asked by la montée 4

i saw it in lord of war

2006-11-02 19:05:03 · 3 answers · asked by krishna s 2

If so , how? (simply!)

2006-11-02 19:03:21 · 15 answers · asked by Anonymous

2006-11-02 18:47:01 · 4 answers · asked by Dund pund se 2

2006-11-02 17:57:30 · 3 answers · asked by freemanjr2 1

2006-11-02 17:44:41 · 2 answers · asked by i<3WL 2

2006-11-02 17:37:24 · 3 answers · asked by jho 1

does anyone know how to find the concentration Sodium hydroxide (.10 M) titrated with .700 grams of KHC8H4O4? three trials were titrated to 38.4,37.0 and 36.1 mL

2006-11-02 17:35:37 · 1 answers · asked by Dund pund se 2

it's JUST balancing, no half reactions or anything like that
[Cr(N2H4CO)6]4[Cr(CN)6]3 +KMnO4 + H2SO4 --> K2Cr2O7 + MnSO4 + CO2 + KNO3 + K2SO4 + H2O

2006-11-02 16:49:19 · 2 answers · asked by sadfjlhasldf 1

in the fuselage with some sort of makeshift water/potassium reactive bomb, causing the plane to go down? What size chunk would you need? Is there a more reactive element (I can't remember my periodic chart)?

2006-11-02 16:39:43 · 5 answers · asked by Jon M 2

The numbers are subscripts. (rb2s is rb subscript and then S.
HF
MgO
Rb2S
BaS
Na2O
Ag2O
ZnF2

Rules are:
First one to answer them all right gets points. Spelling Counts!

2006-11-02 16:39:24 · 6 answers · asked by Anonymous

Silver Tarnishing and photosynthesis,

thanks

2006-11-02 16:35:56 · 1 answers · asked by lawlzlawlzduck 2

What is the formal charge on the O atom in NO+ ??

2006-11-02 16:30:02 · 3 answers · asked by poppa 1

tell how many unpaired electrons are in the following.
sulfer
argon
....
please tell me how to do them! thanks

2006-11-02 16:18:55 · 3 answers · asked by Stephanie 3

Does anyone have any examples?

2006-11-02 16:18:09 · 4 answers · asked by lawlzlawlzduck 2

A 2.747 g sample of manganese metal is reacted with excess HCl gas to produce 3.22 L of H2(g) at 373 K and 0.951 atm and a manganese chloride compound (MnClx). What is the formula of the manganese chloride compound produced in the reaction?

2006-11-02 16:00:01 · 3 answers · asked by goodbye say bye 1

2006-11-02 15:40:14 · 5 answers · asked by JR 1

NH4ClO4 + Al --> HCl + Cl2 + NO + Al2O3 + HOH

i've spent so much time on this it isnt funny

2006-11-02 15:37:56 · 5 answers · asked by sadfjlhasldf 1

2006-11-02 15:20:47 · 3 answers · asked by Myra G 5

2006-11-02 15:18:31 · 2 answers · asked by g 1

The Clues:

1 A watered down drink
2 Why she wears expensive perfume and skimpy dresses
3 A popular gift from your mothers sister
4 a big english theater
5 shock speechless
6 police protection for our security
7 base of the house
8 famous national laboratory
9 the kitchen in a ship
10 a heavy grave
11 a prestegious prize in chemistry
12 blind
13 when a person looses his hair he


Anyone know any of them?

2006-11-02 14:38:15 · 2 answers · asked by Steve W 1

LDA

2006-11-02 14:32:17 · 1 answers · asked by Dhanashri 2