Gold Definition and 189 Threads

Homework Statement Well its 2 questions: Immersing a pair of gold electrodes in a saline solution in the presence of a fixed voltage causes the capacitance to: IncreaseDecreaseRemain unalteredIncrease briefly and then return to its original value Immersing a pair of gold electrodes in a...

Copper ::: 60.7 x 106 S m^-1 Silver :::62.9 x 106 S m^-1 Gold :: 48.8 x 106 S m^-1 Why is the electrical Conductivity of these elements this way? I mean down the periodic table it should increase in case of GOLD but instead Gold is have far less value of Electrical Conductivity.

Homework Statement How close does the alpha particle gets to the nucleus in gold foil scatering experiment?Homework Equations Ek = 2.0 MeV W=F delta x F=(kq1q2)/r^2 W=(kq1q2)/r E=W=(kq1q2)/r The Attempt at a Solution E= (k(79)(2) e^2)/r 2.0MeV= (k(158)e^2)/r 2,000,000 eV = 8.99 Wm^2 c^-2 ((158)...

According to electrochemical series ,gold is the last element thus it is depicted that it is the best electrical conductor.(most of the teachers say that) But according to the internet the best electrical conductor is silver , following copper and gold. Which one is true and why ?

Homework Statement Piece of quartz containing gold weights 102,5g and average density is 7,98g/cm3. Density of quartz is 2,65g/cm3. How much does gold weight? Homework Equations ρ=m/V avg.ρ= m1+m2/V1+V2 The Attempt at a Solution Using average density I find that volume of this piece is...

Homework Statement A piece of aluminum is completely covered with a gold shell to form an object of weight W. When you suspend the object from a spring balance and submerge it in water, the balance...

Homework Statement A man decides to make some measurements on a bar of gold before buying it at a cut-rate price. He find that the bar weighs 2000 N in air and 1600 N when submerged in water. Is the bar gold? Homework Equations B = density* V* g The Attempt at a Solution I tried to use the...

Hello, I was wondering if the offer was still available? I could not find the thread that I initially saw. Thank you.

I asked this in another thread and was told this question should have had its own thread so as to not hijack the other thread. That question was: Has anyone calculated how much if any gold is produced in the sun? which is likely almost none do to the differences between fusion and fission and...

This was one of the alchemists' big quests, and it is evident that it is impossible with the methods that they had available. But how feasible is it to do that with nuclear reactions? Especially nuclear reactions that start with relatively common materials, like hydrogen or carbon or silicon or...

Tests of layered tiles of carbon nanotubes packed with gold and surrounded by lithium hydride are under way. Radioactive particles that slam into the gold push out a shower of high-energy electrons. They pass through carbon nanotubes and pass into the lithium hydride from where they move into...

1. Problem: Gold, which has a density of 19.32 g/cm3, is the most ductile metal and can be pressed into a thin leaf or drawn out into a long fiber. (a) If a sample of gold with a mass of 2.274 g, is pressed into a leaf of 8.678 μm thickness, what is the area (in m2) of the leaf? (b) If, instead...

An alpha particle is thrown toward a gold nucleus. An alpha particle has two neutrons and two protons and a load module 2e, where "e" is the electron charge, while the gold nucleus has 79 protons and a load module 79e. What is the minimum kinetic energy that the alpha particle must have in order...

I want to simulate the absorption spectra of gold octahedra when irradiated by a light source, according to the information I have gathered I can use discrete dipole approximation technique because octahedra is not spherical (in contrast to Mie Theory which is applicable to spherical particles)...

Homework Statement Gold, which has a density of 19.32 g/cm3, is the most ductile metal and can be pressed into a thin leaf or drawn out into a long fiber. (a) If a sample of gold with a mass of 4.713 g, is pressed into a leaf of 6.549 μm thickness, what is the area of the leaf? (b) If...

From ''A Brief History Of Chemistry'' by Isaac Asimov: ''It seemed to Jabir that the different metals were made up of different mixtures of mercury and sulfur, and it remained only to find some material that would facilitate the mixture of mercury and sulfur in the proper proportions to...

Hello, I have a question for electrodeposition of gold. So I tried to electroplate gold on a Si wafer with gold seed layer on it. I used SU-8 as my photoresist to form a pattern. But my electroplated gold was black and granular. Area is 19mm^2 and desired thickness is 50 um. I set the...

Keep your discovery programs to your selves, we are having to suffer things like, American chopper gold diggers, storage wars etc etc. Give us some educational programs please.

Let’s also say that 65% of all diamond rings sold in WV are yellow gold. In a random sample of 20 folks, what is the probability that 12 have purchased yellow gold diamond rings?thank you and I promise this is the last question today.:D

Dear Experts I am using Gold Cap super capacitors. About 3.3 Farads ones at 2.5V. When I charged it to 2.5V, it immediate starts to discharge within a few seconds even when not connected to load. Is this normal? Thank you for reading. Best regards Ramone

Hi, can anyone help me out with the refractive index of pure gold at microwave freguencies? (Specifically something close to 2.4 GHz, or your average household microwave oven) Much obliged!

I am not an engineer so I was wondering if a pound of gold can ever weigh more than a pound of silver under any circumstances relative to the universe as a whole? John

Homework Statement The density of solid gold at 20°C is ρ = 19.3 g/cm3. When it is liquid at 1064°C the density of the liquid state is decreased: 17.3 g/cm3. How much work does a block of gold of mass 407 kg do if it is heated at p = 1.0 atm from 20°C to 1064°C? Homework Equations...

Homework Statement Legend has it that Archimedes first used his discovery to help out his boss King Hero of Syracuse. The king had given 700g of gold to a goldsmith to make him a crown. When the goldsmith brought him the finished crown the King was suspicious that he had defrauded him by...

How to I get the fool's gold out of rocks as to have the gold in one pile the rock in the other? John

Can we make gold from nuclear reaction in the lab? If yes, what are the nuclear equations?

Homework Statement The density of gold (atomic mass 197) is 19.32 g/cm3. Assuming each gold atom contributes one electron to the free electron Fermi gas, calculate the Fermi energy in eV. Homework Equations Fermi energy is given by: E_F=\frac{h^2}{8m_e} \left( \frac{3N}{\pi V} \right)^{2/3}...

The title says it all. Say you have 5 rings, each weighing 18 grams (10% alloy and 90% gold). If you would melt them all and add silver to make it 75% gold, 1) how much silver do you have to add? 2) Does melting 5 rings with 18grams each give 90 grams in total? 3) is this equation...

http://www.lasvegassun.com/news/2012/sep/18/nv-quiet-recluse-gold/

Hi, I can precipitate gold dissolved in aqua regia if the gold is just pure.I use sodium metabisulfite.However,if I dissolve the gold from ore in aqua regia,I cannot precipitate the gold.What's wrong?Might other metals or mud in the soil spoil it?Does anything prevent precipitating?Any help...

In May of this year I received a First Class Honours degree in physics with astrophysics (UK system which is roughly equivelent to 4.0GPA). I thought this was not a bad acheivement - although I knew that there were 2 other members of the class who had done much better than me. Today my...

Good day sirs. I was wondering, how is gold located? I mean, do they use any machine to locate it I am referring me to depths of over 10 meters up to 2 kilometers

Mobile SIMcards are coated with Gold, why we can't use other metals or Alloys for conductivity.

What's stopping entrepreneurs from using fission - taking mercury, for example, or any heavier element for gold/silver - and creating gold and silver from it? Do you think there will come a day when this is commercially viable? Any guesses when?

With all the scientific and technological capabilities we have, why can't scientists make Gold? If all elements came from just a few elements early on in the big bang, why can't we simulate it somehow? Is it that we can, but its just not cost effective to mass market it and drive down the...

Homework Statement A jeweler has made a crown of an alloy of gold and copper. The crown weighs 0.358 N when measured in air and 0.338 N when submerged completely in water. The density of water is 1.00x10^3 kg/m^3, the density of copper is 8.92X10^3 kg/m^3, and the density of gold is 1.93x10^4...

A few weeks ago, I got a titanium crown next to a gold crown. Now I'm getting weird reactions in my mouth. I emailed my dentist and will consult with him of course (PF rules and all). I'm not trying to get advice on what to do but I am wondering if it's possible from a periodic table view...

does this even make sense? I mean is gold located/formed in a specific depth range? or it virtually could be found anywhere? the next question how to setup a relatively small budget mine with underground levels/rooms? :D

I have always just assumed that now creating gold from particles was possible, but can they really do it? It must require a lot of pressure to get the protons close enough together for the strong force to finish the job, since the repulsive electromagnetic force. Do they do this? than just...

Homework Statement In an experiment carried out with a beam of thermal neutrons it is found that on traversing a 2mm thick foil of 197Au, some 70% of the neutrons are removed. What is the total thermal neutron cross-section for this isotope of gold? (Density of gold: 19300 kg m-3) Homework...

number of atoms in FCC gold cube with only the radius given! 1)it is given that the radius of a gold atom sphere is 144.2 pm, gold is packed in an FCC manner Give the ratio Ns/Nv as a function of L (gold cube side) and a parameter of FCC latice, knowing that Ns is the number of surface...

Hello i need help in this question it is given that the radius of a gold atom sphere is 144.2 pm, gold is packed in an FCC manner Give the ratio Ns/Nv as a function of L (gold cube side) and a parameter of FCC latice, knowing that Ns is the number of surface atoms and Nv is the...

I found a lot the the surface plasmon on prism geometry are using gold for metal film, and part of it are using silver. Why we need use gold or sivler as a metal film, is it about the condutivity?

Hi, guys! Gold is usually used as reference element to calibrate the detector in XPS due to the charge effect, why is Gold so specific? So what element can be the reference element for XRF and LIBS? Thanks a lot!

Homework Statement Gold, which has a density of 19.32 g/cm^3, is the most ductile metal and can be pressed into a thin leaf or drawn out into a long fiber. (a) If a sample of gold, witha mass of 27.63g, is pressed into a leaf 1.000 µm thickness, what is the area of the leaf? (b) If, instead...

Actually, it is smaller. Is is more like glitter-sized. What process do I use to extract it?

Homework Statement A cube of gold (resistivity ?R = 2.44 10-8 O m, density ?D = 1.93 104 kg / m3, and specific heat c = 129 J / kg °C) that is 3.5 mm on a side is connected across the terminals of a 40-µF capacitor that initially has a potential difference of 340.0 V between its plates...

Homework Statement If the radius of the gold nucleus is 6.47 fm, and the radius of the α particle is 2.36 fm, then what is the minimum required kinetic energy for the α particle if we want the two nuclear surfaces to touch in a head-on collision? Homework Equations Ue=(kq1q2)/r The...

Hi everybody, I would like to know if someone could explain to me what happens to the refraction index of gold at grazing angle (X-ray applications), and particularly the band structure explanation (if you have it!)... Indeed, I heard that the x-ray telescopes were made of parallel mirrors...

http://en.wikipedia.org/wiki/Synthesis_of_precious_metals" I'm no nuclear physicist or anything but with all the tiny bits of nuclear waste we have in all our electronics, paints, materials, etc. it seems that turning mercury to gold would be fairly easy to do with things you would otherwise...