|
|
Post by tileman2 on Dec 20, 2015 18:24:03 GMT -6
jim:
love the link; that is what my chemistry books do: this applies here, and that applies here. We both had the dots, just needed someone to show how they connected.
No, nothing is being oxidized in that equation: it is a formulation for reactants: not products.
2 (moles) ZNO plus one mole of SiO2 or 67.67% ZNO plus 33.33% SiO2. All chemical reactions are shown in parenthesis. If an element gains an electron: then it is shown as -1 ( or however many were gained.). If an element has been reduced: then it is +1. Odd way to express the reaction; just the opposite of what we are trained math wise. ZNO(-1)SiO2 would express that the ZNO picked up one ion from the SiO2. You do not have to put +1 behind the SiO2 because the equation already states that the ZNO has a donor electron, and SiO2 is the only other element in the equation. SiO4 would actually represent a polymorph of SiO2 such as Wollstanite SiO3 or Talc SiO4(O10): but then you would also have to add their elements as well. If they precipitated silica you could have SiO4 as well.
Tom
|
|
|
|
Post by tileman2 on Dec 20, 2015 18:32:18 GMT -6
Best periodic table I have seen on the net: show atomic weight, electron affinity, electronegativity, plus descriptions. www.ptable.com/Tom |
|
|
|
Post by jfox on Dec 20, 2015 19:11:43 GMT -6
|
|
|
|
Post by tileman2 on Dec 20, 2015 22:10:00 GMT -6
but you wrote 2 ZNO + SiO2 = that is formulation. The 2 before indicates amount.. the 2 after means result (product)
|
|
|
|
Post by jfox on Dec 21, 2015 10:05:27 GMT -6
the last 2 is supposed to be a subscript,computer wont let me. 2 moles of ZnO(Zinc Oxide) + 1Mole of (Silica) SiO2 = one mole of (willimite) Zn2SiO4 reactants on the left side of the equal sign and product the right this article explains the covalent nature of the silica bond i'm still not sure whats happening with the zinc geology.about.com/od/glossaryofgeology/g/Silica-Tetrahedron.htm |
|
|
|
Post by mohawkpiper on Dec 21, 2015 10:34:14 GMT -6
Hi Jim,
Right above the reply box there are a bunch of buttons and one is a subscript button. It is the big A with the little s. Make sure to turn it off after you use it. Or type everything out first then highlight the subscript later then push the button.
Hope i get this right...
2ZnO + SiO2 = Zn2SiO4
G
|
|
|
|
Post by jfox on Dec 21, 2015 11:11:48 GMT -6
Thank you Greg
|
|
|
|
Post by tileman2 on Dec 21, 2015 18:58:00 GMT -6
Jim:
I should have known that because I tried subscript awhile back and could not do it.
from the article; "Its hunger for electrons"... what we call "affinity.". The glaze books and articles use the word "affinity", dropping out the word before it: "electron affinity."
Tom
|
|
|
|
Post by tileman2 on Jan 4, 2016 18:53:12 GMT -6
Jim:
Having read your 85 page guide to making red crystals I realized; we must like reading really boring sh**. However, decided to try the old ruby red from the classic glass blowers recipe: equal parts selenium, candium sulfide, and borax. Here are the results- nadda- zilch, got nothing. My special order did come in though- the ultimate melt your eyeballs flux: anhydrous calcium borate. 42.5% boron and 37% calcium. We shall see how it melts Moly at cone 6? If that does not work, will throw in some cryolite and melt the whole kiln-- who cares. Maybe a dash of yellow cake just in case- then I will have Moly crystals that glow in the dark.
Tom
|
|
paul
Junior Member
Posts: 51
|
Post by paul on Jan 4, 2016 19:25:11 GMT -6
"Having read your 85 page guide to making red crystals I realized; we must like reading really boring sh**. However, decided to try the old ruby red from the classic glass blowers recipe: equal parts selenium, candium sulfide, and borax. Here are the results- nadda- zilch, got nothing"
Tom,
How much Selenium did you use......... it takes a high percentage to get red, otherwise you get white, not sure what the Cadmium is going to do to it, but I think you need 6%, ...maybe as much as 10%
selenium to get red.
I tried some and got a red tip on the top of my vertical tile, the rest of the tile was white, don't remember exactly the percentage I used
|
|
|
|
Post by tileman2 on Jan 4, 2016 21:32:22 GMT -6
Paul:
From the glass dictionary by Charles Bray: .86% each- cadnium, selenium, and borax. Also did one with double that. Yes, I got a pure white and a slightly off white. Some time this week, will burn some samples with..see where this old dog leads. Would be great to get a nice ruby red without the reduction.
Tom
|
|
paul
Junior Member
Posts: 51
|
Post by paul on Jan 4, 2016 23:23:43 GMT -6
This is the first sentence in the second paragraph of the article Jim posted in his posting on Red Glass.
It has been found that by combining molybdenum and selenium in alkali-lime-
silica glass under reducing conditions, a red pigment can be obtained.
It clearly states you need reduction when using Selenium, try reducing your tiles, see if anything changes.
|
|
|
|
Post by tileman2 on Jan 5, 2016 8:57:29 GMT -6
That is called wishful thinking... did the reduction on the two test samples.
Tom
|
|
|
|
Post by tileman2 on Jan 6, 2016 17:26:56 GMT -6
Well, finally getting to the place for doing some serious reductions. Played with it a bit, but finally got a bunge ready, tubing.. etc. So best temp is still 1350F? Length of time 10 mins? Best medium?// alky, mineral oil, veggie oil? Thoughts, opinions?
Edit.. forgot one... drip rate?
Tom
|
|
|
|
Post by jfox on Jan 6, 2016 22:46:21 GMT -6
propane ( this is a gas kiln), but dont blow your self up, I have a small 1 '' hole in the wall at the floor level of the kiln after i start reducing i take a tourch and light the fumes coming out then i back off the gas till i can just maintain a flame coming out of the hole and i know i have a solid reduction
|
|
