March 24, 2023, 05:25:51 AM
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Undergraduate General Chemistry Forum / Ionic Equation Question
« Last post by chickennuggetman225 on Yesterday at 07:01:31 PM »
I must find the total ionic equation of this formula:

Cu(OH)2(s) --> CuO(s) + H2O(l)


All the videos i've seen say to split all (aq) substances to find the total ionic equation but this is different.
2
Analytical Chemistry Forum / Re: Reference Cubette
« Last post by Hunter2 on Yesterday at 12:25:46 PM »
The blank should be done with the same matrix. So the best is to make one with  everything in without the phosphate.
But you can compare a measurement with distilled water, how much is difference to Zero.
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Analytical Chemistry Forum / Reference Cubette
« Last post by kobold on Yesterday at 11:16:51 AM »
Hi!

I got a double beam spectrophotometer. I am using a method of phosphurus determination using Ammonium Hepta-Molybdate at 880 nm.

My question is simple: is it correct if I fill the reference cubette with distilled water (because it is the solvent I use)?
Or it would be better to use a blank (everything I use to make the samples without the sample) ?

I am kinda leaning to the opinion that it does not matter which I use but I want your opinion!

Thank you all for your attention!
4
High School Chemistry Forum / Re: Properties of Solids Lab Help
« Last post by Borek on March 21, 2023, 05:38:33 PM »
-> solubility - using boiling water for all as ionic solids break into ions & conduct electricity

You actually don't need boiling water for the test.

Quote
- hardness - using a hydraulic press/Rockwell testing

Even just trying to scratch with a knife will give some info.

Quote
SOME OTHER THINGS WE CAN USE (but I'm unsure as to what we can use it for): a thermal camera

Not sure what for. Heat conductivity to some extent perhaps.

Quote
2. WRITE A HYPOTHESIS for ONE TYPE of solid with a brief explanation.
-> I'm having some trouble with where to start for this?

It can be really anything, like "harder solids have higher density". Doesn't matter if it is true, you are about to test it to either prove, or disprove.
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Hello,

Is there any suitable for home use solution to copper plate on top of zinc alloys?
I tried copper sulfate, but it corrodes the surface of the parts.
Tying actially to refinish a part, it corrodes where the base metal is exposed and I get ulcers on the surface.

Could that solution work?

Copper sulphate 35-40 gms,
Potassium sodium tartrate 180-190 gms,
sodium hydroxide 50-60gms,
20 °C temp.
0,3-1,5 A/dm2

Kind Regards :)
6
High School Chemistry Forum / Properties of Solids Lab Help
« Last post by Krystalsnow2013 on March 20, 2023, 06:23:30 PM »
Consider FIVE types of solids:
Ionic (NaCl)
Metallic (Ca)
Covalent Network (Quartz, SiO2)
Polar Molecular (sugar, C6H12O6)
Non-polar molecule

RECALL THE PHYSICAL PROPERTIES -> hardness, brittleness, the conductivity of electricity and heat, melting and boiling points, solubility in water, etc.

1. Design an experimental procedure to test these properties with the procedures below.
-> the ones I have so far
- ionic solids -> use NaCl and dissolve in water to test the solubility
- conductivity - by putting the solid under two free ends of the wire
-> solubility - using boiling water for all as ionic solids break into ions & conduct electricity
- brittleness - using a hammer or any other form of stress (if brittle, tends to break under stress)
- hardness - using a hydraulic press/Rockwell testing
- melting/boiling point - add heat to a sample after placing in a beaker or test tube to test

SOME OTHER THINGS WE CAN USE (but I'm unsure as to what we can use it for): a thermal camera

2. WRITE A HYPOTHESIS for ONE TYPE of solid with a brief explanation.
-> I'm having some trouble with where to start for this?

3. Design a Table of Observations for your experiments.
-> I'm unsure as to how to do this??
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Other Sciences Question Forum / Re: Concrete Densifier PT2
« Last post by cluelesswonderer on March 19, 2023, 09:17:04 PM »
Thank you for your responses. I actually thought to myself that something like dioxane and ethylene oxide might evaporate. I'm assuming anything residual wouldn't be a concern unless I was actively licking the floor :P lol
8
Physical Chemistry Forum / Re: NaOH & Water solution superheated
« Last post by Cicci on March 19, 2023, 06:16:33 AM »
Thanks for response, I appreciate it.

Yes, its more dangerous than water for sure, just wondering how is it related to NaOH regarding precondition for superheating to exist.  For water it is more probable to happen with destiled water than tap water, but for NaOH I have no ide, so any info around this would be valuble.

Regards
9
Organic Chemistry Forum / Re: Nitration.
« Last post by Borek on March 18, 2023, 03:33:28 PM »
Could you write the nitration products of these compounds I would be very grateful I need them very much ? ;)

You were already given clear hints.

We don't do homework for people. Please read the forum rules.
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Organic Chemistry Forum / Re: Nitration.
« Last post by Oso32105 on March 18, 2023, 10:55:54 AM »
Sorry, I meant the nitro group.Could you write the nitration products of these compounds I would be very grateful I need them very much ? ;)
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