anyone know what the lead measurement stands for?  i'ts ug/dl.  what does ug sthad for?
952305
Micrograms per deciliter.  10ug/dl is the limit for the general public.  Over 50 and you need to do something about the source.  Over 100 you WILL start to have health problems.
920352
Did you measure the absorbance of a standard in addition to the unknown sample?\n\nIf so, you could plug the values into (As / Au) = (Cs / Cu)\nWhere\nAs = Absorbance of the Standard\nAu = Absorbance of the Unknown\nCs = Concentration of the Standard\nCu = Concentration of the Unknown?\n\nAlternatively, did you get a value for the molar absorptivity of PNP at the wavelength you used? \nIf so, you could plug it into\n\nA = (epsilon)(b)(c)\n\nWhere\nepsilon is the molar absorptivity,\nb is the length of the path through which the light passed,\nc is the concentration of the chromogenic substance.\n\nAnd you could rearrange that to solve for c.\n\nHope it helps
387399
Pb2+ + Cl- ---> PbCl2\n\nWe know that the lead in Pb(NO3)2 has to have a 2+ charge because a nitrate ion has a 1- charge, so two of them is a 2- charge.  The entire compound must have no charge, so a 2+ charge is assigned to the lead. \n\nBoth compounds Pb(NO3)2 and NaCl dissociate (they are both soluble), and because nitrate and Na+ ions are always soluble, they can be ignored in a net ionic equation.
928283
I belive your u is the Greek letter mu, the prefix for micro, meaning 10^(-6).  The term ug would therefore equal 1/1,000,000 gram, which is 1/1,000 of a milligram, abbreviated mg.\n\nSo, 50mg = 50,000 ug
449770
Teaspoons are a measure of volume, and grams are a measure of weight.  Unless you know the density of the material, this cannot be done.
851017
B)   PbS  use the solubility rules. all leads are insoluble except with NO3, ClO4, and SO4....there is a list of solubility rules.
10210
The number is a rating for the hardness of the lead/graphite.  Lower numbers are softer, higher numbers are harder.  The #2 is optimal for optical scan sheets and wear.
176106
No, because pencil 'lead' is no longer made of lead. It's now made of non-toxic graphite. I also have a small piece in my skin.
1145807
Well, I can tell you that the gram is pretty much a made up unit.  At some point, someone cast a metal weight and called it a gram. It still exists somewhere, they keep it under a glass dome to avoid compromising its accuracy with dust.  Strange as this sounds, it's actually true. You might wanna do a little more research on it though before you write an answer.
793636
shawty's NOT good at stoichiometry...has made a fundamental error in the final line so end result is rubbish...\nhow can you end up with MORE Cu than you started with when it's 2 moles : 2moles? \n\n(8/159)x 127 = 6.4 g
200877
I don't know about u/d/t, but u/t/d stands for "under trust dated."  It's included in the signature block when a trustee (who is the one with legal authority to sign a document on behalf of the trust) signs a document.
93031
Check this out...\n\nhttp://home.inter.net/eds/paper/inchmetric.html
740420
Wait a minute everybody!\nthose vertical lines,( lyl ) could mean absolute value!!\nHelloooo?\nso the answerSSS could be 9 and -9\nsheesh!
334151
Lead melts at 327.5 °C\nAluminum melts at 660.0°C\n\nIf you had to ask for this information here, and not look it up yourself, you shouldn't be melting lead in the first place.
706464
what do u mean by that, symbolicaly it is  gm/ml or g/ml
137292
You didn't really give me too many options with this one.  Increase or increase?  I think I'll have to go with "increase."\nSeriously, if a pipet is dirty, most likely it is contaminated with a salt compound, which would contribute to the density of something you were measuring out with the pipet.
191749
i agree that it's probably lead.  lead is very dense, so your things should feel very heavy for their size.  you can verify this by a couple methods:\n\n1.  get an accurate scale and measure the weight of a piece.  then get a graduated cylinder from your school and fill it partway with water.  dunk the same piece of the metal into the water and see how much the volume changes.  divide the weight by the volume to get the density.  compare this to the density of lead which is 11340 kg/m^3 or 11.34 grams/mL.\n\n2.  if you have a voltmeter, do the following:\n - get a tub of water and dissolve some salt in it\n - cut out a strip of aluminum foil and immerse one end in the water\n - take your mystery metal and immerse one end in the water\n - make sure the two metals aren't touching\n - connect one probe of the voltmeter to the aluminum, and the other probe to the metal.\n - aluminum has an electrode potential of 0.13 V and aluminum has an electrode potential of 1.66 V, so if lead is the metal then the voltmeter should read 1.66 - 0.13 = 1.53 V.\n\nsounds like you are going to have some fun!\n\nalso, lead is toxic so wear gloves and wash your hands after you handle it.