Lead Definition and 292 Threads

Hey everyone, I have a question about lead and mercury poisoning in the human body. What actually happens in the human body that causes lead and mercury to be poisonous? Thanks!

Homework Statement Excess electrons are placed on lead sphere with mass m=8.00g so that net charge becomes q=-3.20*10^-9 C. How many excess electrons are there per lead atom? Homework Equations The Attempt at a Solution Have found: number of excess electrons= 2.00*10^10...

Hi, I will be investigating the concentration of lead in Henna, a traditional moroccan substance we apply to our hands, for my extended essay. In order to do so, I have to derive method(s) by which I can easily measure concentration of lead. If you have any idea, please let me know. Your...

could anyone tell such a method how one can make stable lead from stable bismuth?

What happens to lead then you overheat it beyond its melting point, and what metal or chemical does it become then?

I have a problem I'm working on that I'm a bit stuck on. In this problem we are allowed to use Taut Con in our Fitch proof. The goal is to prove the following from no premises: ~∃x∀y ( P(x,y) ↔ ~P(y,y)) My initial thought is to begin a subproof with the problem itself, except without the...

This is the question... What is the maximum mass of lead you could melt with 1000 J of heat, starting from 20C? I know that for lead Tm = 328 degrees C Lf (j/k) = 0.25 x 10 ^5 Tb = 1750 degrees C Lv = 8.58 x 10^5 but I'm not really sure what i need to use. Q = Mc delta T but...

I want to learn the GFD lead acid batteries used in NPP. Have Exide and Deka ever supplied for NPP, or who are the main suppliers in this field? We know VRLA betteried dominate the market now, but have this type ever been use in NPP? As for UPS, do bettery suppliers provide UPS together...

The specific heat capacity of solid lead is 0.159J/g°C, the molar enthalpy of fusion is 5.0kJ/mol, and the melting point of lead is 328°C. Calculate the total energy required to change 100g of lead at 25°C to molten lead at it's melting point. I don't even know where to start, I know...

Some time in the past my father took it upon himself to due a little plumbing. He decided that it was okay to use solder that contained lead to connect two pipes right near the output of the water heater. His reasoning was that we would not get lead poisoning because we could always use cold...

when tennis ball spins sideways like a hurricane. I have seen that if you spin it a little, it turns one way, when you spin it more, it turns the other way. So here are my questions. 1. Will there come a point as you are inc. angular velocity that it will not change direction anymore? 2...

A friend of mine emailed me this question: At first glance, I expected it to be easy, but I'm really not sure what the answer is! Drafting in a car works because the rear car pushes a high pressure area in front of it, partially filling the low pressure area behind the lead car, reducing...

How can we let things like this happen? "Cool your home, warm the planet. When more than two dozen countries undertook in 1989 to fix the ozone hole over Antarctica, they began replacing chloroflourocarbons in refrigerators, air conditioners and hair spray. But they had little idea that...

Can someone please help me solve this?? A 5 gram bullet traveling in 20 0C air at 300 m/s strikes a flat steel plate and stops. What is the final temperature of the lead bullet?(Assume all heat is retained by the bullet. The melting point of lead is 327 0C. The specific heat of lead is...

This sounds good, but who are they kidding, the new Iraqi govenment officials can't even travel outside of the greeen zone. Policemen are issued a single Glock handgun, and soldiers are issued an AK47. On the other side the insergents have morters, RPG's, rockets and heavy machine guns...

Okay, the question I'm suppose to answer is: If the attenuation coefficent of Al is 1.73/cm for soft-xrays, what percentage of X-rays penetrate a piece of lead 3.00mm in thickness . . . What I seem to have is I = Io*e^(-ux) I believe u = 1.73/cm and x = 3.00mm. My 3...

Given: latent heat of fusion of water is 333000 J/kg. A 3.37 g lead bullet at 27 degrees C is fired at a speed of 272 m/s into a large block of ice at 0 degrees C, in which it embeds itself. What quantity of ice melts? Assume the specific heat of lead is 128 J/kg x C. Answer in units of g...

use you accepted value for the solubility product of lead 2 chloride to determine the solubility of lead 2 chloride in mol/L and g/L the accepted value is ksp=1.2*10^-5 Ksp=[Pb] [Cl]^2 1.2*10^-5 = (x) (2x)^2 x=0.014 mol/L 0.014 mol/L * 276.1 g/mol =3.98 g/L I don't know if I...

HELP! In this experiment I measured the initial mass of a piece of Al and then i put it into a beaker containing 100.0 mL of saturated PbCl2 The concentration I calculated for Pb is 6.12 *10^-^5 mol/L The concentration I calculated for Cl is 1.224* 10^-^4 mol/L Therefore my Ksp= [Pb]...

i need help answering some chemistry questions..and i need these answers asap. 1. I need three reasons why the specific heat of lead is so hard to find? and the second is 2. Three reasons why an error could have occurred in our calorimetry lab? Thank you chemistrygirl09:smile:

Would it be too chaotic to allow for stability to arise? would it be "dead"?

Just reading a textbook and came across this interesting question: "a daring lab instructor in a demonstration dips his wettened fingers into molten lead (327C) and withdraws them quickly without getting burned. How is this possible?" I was thinking simply that the water on the fingers...

what is the product of the reaction: PbO + NaOH -> ? or PbO + NaOH + H2O -> ?? is there any difference?:frown: thanks

1. A football is kicked with an initial speed of 22m/s at some angle above the horizontal. It travels 45 meters horizontally before hitting the ground. a. At what angle was the ball initially kicked? b. How long does it stay in the air?

A lead ball is dropped into a lake from a diving board 5.00 m above the water. After entering the water, it sinks to the bottom with a constant velocity equal to the velocity with which it hit the water. The ball reaches the bottom 4.60 s after it is released. how deep is lake?

Hello everyone, I was poor on TLC before, and am poor now :smile: I want to ask a question to you guys. Please look at the attached zip file with a tif image. My question is very simple: Is it possible to fully isolate the impurities (yellow spot and light olive-mustard-colored...

Hi I was reading an article in the New Scientist, about how fusion can be created in a device no bigger than a coffee cup. It said that an electrically polarised piece of deuterium doped lithium tantilate (don't know if this is the right spelling) placed in a strong electomagnetic field...

Can mixing (in series) old cells with new cells of the same voltage and rating damage the new cell? If so why? The cells are recharable.

A 5-g lead bullet traveling in 20 C air at 300m/s strikes a flat steel plate and stops. What is the final temp of the lead bullet? (Assume bullet retains all heat.) The melting point of lead is 327 C. The specific heat of lead is 0.128 J/g C. The heat of fusion of lead is 24.5 J/g. a. 227...

Where does it point?

This idea came out pondering the question if scientific research is limited in what it can achieve. Evolution is the process that can lead to the organization of matter as complex as the human mind. Scientific research can lead to different (not necessarily as complex) organizations of...

In angioplasty, balloon is inserted on catheer and expanded, causing flattening or tearing of the rigid atheromous plaque and thus allow the vessal to return to its shape, often aided by a stent. But surely, any tears in a plaque may lead to cloating? After all, this is what we usually worry...

If I were to put about 80 g of lead into 80 g of water boiling at 100 degrees, after about 5 minutes, would the lead attain approximately 100 degrees or would it be significanty less?

Hi guys and girls, I've been going thorugh some problems in cutnell & johnson on heat and temperature and I have become stuck on this question. Can anybody help with this? Its from Cutnell and Johnson 5th p375 Q18*. A lead sphere has a diatmeter that is 0.05% larger than the inner diameter...

A 4.2 g lead bullet moving at 260 m/s strikes a steel plate and stops. If all its kinetic energy is converted to thermal energy and none leaves the bullet, what is its temperature change? --- I don't even know what formula to use or how to start. I could get force, by multiplying the mass...

Can anyone please expalin to me how it's possible for wormholes to lead into different parts of space, and even time? Thanks.

Apparently, Iran's defense minister is a fan of this preemptive war stuff, and figures that if using preemptive war is good enough for the USA, that it would be good enough for Iran, and is thinking of preemptively attacking Isreal, specifically their nuclear facilities. Also, due to American...

This one is different, and it is driving me crazy almost as bad as the other two. A lead sinker is attatched to a round platic sphere. If the sphere floats so that it is half submerged, and has a weight of 1oz. (6.25 * 10^-2lb) and a radius of 1in, (8.33 * 10-2ft) find the volume and weight...

Musket balls were once produced by dropping a measured amount of molten lead from a high tower into a trough of water. What various abberations from musket ball sphericity would you anticipate, and with the technology present how might you improve on this process?

Is it possible for this to happen? As far as I know the only way to change elements into other elements is through radioactive decay, and fusion and fission yeah yeah. But I also know that elements with atomic numbers higher then lead's tend to decay into lead and just kind of stop there...

Zoobie seems to have a rather serious LEAD BUTT problem! She can't seem to jump up onto anything that doesn't have material that she can claw her way up on! (It actually may be a blessing, as it allows our two OLD kitties to escape her 'high activity kitten' periods). Does anyone else...

The rainforest produces a good amount of o2 (exactly how much I'm not sure), could deforistation of the rainforest lead to such a decrease of o2 in the air that fires wouldn't be able to light? About how much could the percent of o2 in the air vary before fires stopped being able to burn?