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Why are carbocations with sp3 hybridisation highly unstable? [duplicate]

Why is it that sp3 hybridized carbonium ions do not exist? Or why are they very difficult to form? For instance, nucleophilic substitution in bicyclo compounds at the bridge head carbon is not very ...
3
votes
1answer
3k views

Best consumption-safe liquid for caffeine solubility?

The question is simple: What human-consumption safe liquid has the best caffeine solubility? It's 200mg/10mL of water. That's a lot of water for one dose! I found some ramblings on a fourm stating ...
0
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1answer
115 views

Electrolysis Anode equation

In the electrolysis of $\ce{Na2SO4}$, is it valid to write the anode half-reaction (oxidation) as $$ \ce{OH-} \rightarrow \ce{H+} + \frac{1}{2}\ce{O2} + 2\ce{e-} $$? My book says it's $$ \ce{H2O} \...
18
votes
3answers
58k views

What is hydrogen-rich water?

My question is: Is hydrogen-rich water true? I am aware of the alkaline water. I have read several articles in the Internet regarding this kind of water but I cannot seem to be convinced. Wikipedia ...
1
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1answer
249 views

Molarity exercises [closed]

Can anyone direct me to a good book with lots of molarity exercises, i really want to practice this and would like to find as many types of exercises involving molarity. I of course did google this ...
0
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1answer
154 views

Hydrogen ozonide existence

Does the hydrogen ozonide exist? I mean if this compound could be found in Nature $$HO_3$$ I am interested in the theoretical or phenomenological of such a chemical compound...
-1
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1answer
100 views

ions proportion [closed]

I have a precipitation reaction of this form: $\ce{Ca^{2+} + CO_{3}^{2-} → CaCO3}$ How many mole of $\ce{Ca^{2+}}$ ion is contained in a 200ml solution? I'd like to know how to calculate this, ...
0
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1answer
692 views

Formation of coordination complexes?

I'm having trouble understanding how exactly coordination complexes are formed. Compounds such as $\ce{[Cu(H2O)6]++}$ are the ligands filled into the empty 3 of 4p orbitals+ 1 of 5s orbital + 2 of ...
1
vote
1answer
1k views

Chemical shift value and proton NMR spectroscopy

I am a bit confused about what chemical shift value signifies in proton NMR spectroscopy. If the proton of the standard substance TMS absorbs X Joules of energy to go into resonance, than a substance ...
1
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2answers
332 views

Ideal Gas Law, P,T,V Change => adiabatic?

Given the expansion of an ideal gas, Pressure $P$, Volume $V$ and Temperature $T$ change from $P_1$, $V_1$, $T_1$, to $P_2$, $V_2$, $T_2$. a) Does the standard ideal gas law predict correct end ...
3
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2answers
3k views

What are ketoximes?

I am reading a book which is saying about the Syn-Anti nomenclature of oximes. It is showing this molecule to be Syn-methyl-ethyl ketoxime. I can't understand what is a ketoxime and how is there ...
1
vote
1answer
122 views

A full verion of the periodic table (For computer game)

I am looking for a full set of data on every element on the periodic table. (and if possible those only speculated about) When I say full I mean everything. Electron configurations, Valence electrons,...
1
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2answers
3k views

Why do amorphous substances have different values of physical properties in different directions?

Today my teacher taught about amorphous and crystalline substances. Crystalline substances are said to have different values for physical properties (like speed of light, electrical resistance, etc) ...
2
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1answer
2k views

Memorize Transition Metal Electronic Ground State

In the course of my undergraduate studies it has become clearer and clearer that it is quite helpful to know the ground electronic state of transition metals by heart, if only to speed up the process ...
0
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1answer
46 views

Gas law with molecules at the same time

How many grams of oxygen are present at 25.0 C in a 5.00L tank of oxygen enriched air? The total pressure is 30.0 atm and the only other gas is nitrogen with a pressure of 17.0 atm. After converting ...
0
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2answers
169 views

Gas law and moles

A sample of solid magnesium reacts with excess $\ce{HCl}$ solution to form hydrogen gas. The sample of gas measures $1.628\ \mathrm{L}$ at $22.0\ \mathrm{^\circ C}$ and $0.930\ \mathrm{atm}$ of ...
0
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4answers
4k views

Gas Law problems with stoichiometry

Consider the following reaction : $\ce{H2 + Cl2 -> 2HCl}$ A) If you have 15.00 liters of hydrogen reacting with 10.00 liters of chlorine at STP, how many liters of HCl would you produce? B) What ...
2
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4answers
67k views

How do I find molar mass using gas laws? [closed]

A gaseous sample of a compound has a density of $\pu{0.977 g/L}$ at $\pu{710.0 torr}$ and $\pu{100.00 ^\circ C}$. What is the molar mass of this compound? When I worked the problem I got $\pu{29.9 g/...
12
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2answers
3k views

Sources for raw 1H-NMR data?

Where can one find examples of raw data for an 1H-NMR spectrum? This may sound as an odd request, so I'll give some context. I have found lots of images of spectra such as this: where you can see ...
18
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5answers
64k views

The Lewis structure of HNO3

So I was checking the structure of nitric acid in Wikipedia, however I couldn't quite fathom why it looked like that because it seemed to contradict the following statement: A Lewis structure with ...
3
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1answer
3k views

De-/protonation of R-OH group by acids and bases

Let $\ce{R-OH}$ be a group with a $pK_a$ of 16. Are the following two statements correct? In principle, the group can protonate another acid with $pK_a > 16$, and so (put differently), any "acid" ...
-1
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1answer
1k views

How can zinc metal still be present after the reaction? [closed]

A $\pu{15.8 g}$ strip of zinc metal was placed in $\pu{100 ml}$ of silver nitrate. When the reaction was complete, the strip of zinc had a mass of $\pu{13.1 g}$. What was the concentration of the ...
-1
votes
1answer
3k views

Why should colorimetric titration of a weak acid with a weak base not be done in laboratory? [closed]

Why should colorimetric titration of weak acid with a weak base (or vice versa) not be done in laboratory? How can I draw a pH graph for this?
2
votes
3answers
4k views

In nuclear chemistry, how does a neutron split to form a proton and an electron?

I'm studying radioisotopes at the moment and balancing nuclear reactions isn't making sense in that more matter is coming out of the equation in negative β decay equations : $^\textrm{14}_\textrm{6}\...
6
votes
2answers
950 views

Why does water cause a jet flame when poured over a bunch of tealights?

A neat party trick (typically for outdoors) is to build a pyramid of tealights, let them burn for a while and then pour a bit of water over it and see a large jet flame shoot out (see e.g. this ...
0
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1answer
77 views

The proteins “eluted” or “were eluted”?

In describing proteins, I've written "the proteins detached from the [Ni-IDA] matrix and were eluted from the column" Should I use "were" or can something simply "elute" ?
2
votes
1answer
801 views

Volume of gas needed to heat air in room

How much methane gas ($\text{cm}^3$) is required heat $150~\text{m}^3$ of air by $10~^\circ\text{C}$? Please help! I thought this wouldn't be too difficult but I've been stuck for at least an hour ...
2
votes
1answer
331 views

X-ray fluorescence: where do expelled electrons go?

I'm studying the XRF method cause I'm about to use a WDXRF spectrometer at college so I'm getting all the information about the physics and chemistry behind it. I'm just curious about one thing, as ...
3
votes
1answer
1k views

Why distinguish between polarity and hydrophobicity?

I have yet to see an example of a molecule that's both polar and hydrophobic or that's both non-polar an hydrophilic. If no such molecule exists, why use the terms "hydrophilic" and "hydrophobic" at ...
0
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1answer
252 views

Calculate partial pressure of gases at equilibrium

I have the reaction $\ce{CO_{(g)} + Cl2_{(g)} <=> COCl2_{(g)}}$ where $K=4.5\times10^9$ at $100\ \mathrm{^\circ C}$ The first question was to find $K_p$ which I know is $K_p=K(RT)^{\Delta n}$ ...
0
votes
1answer
151 views

Quantifying Ascorbic Acid in Soft Drink

I have access to a GC/MS, FID, and a spectrophotometer. My first thought was to derivatize with trimethylsilylating agent, then run it by GC. Unfortunately the water is problematic. Heating it is ...
17
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3answers
812 views

Have there been no advances in the determination of effective nuclear charges since Clementi and Raimondi in the 60s?

Effective nuclear charge is a very important concept in chemistry, and is the basis for the qualitative explanation of many observed chemical and physical properties, including several periodic trends....
10
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1answer
275 views

Standards for drawing chemical molecules

I'll preface this by saying I haven't had a chemistry class in 10 years and molecular structures are not my thing. But I'm submitting a revision to a journal paper where I need to include figures of ...
2
votes
2answers
60k views

What's the difference between enthalpy of combustion and heat of combustion?

Wikipedia has two different pages for enthalpy of combustion and heat of combustion. Their definition is the same and they use the same symbol $\Delta H_c^\circ $ It says that enthalpies of ...
0
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1answer
64 views

Concentrations at equililibrium

At $25 ^\circ C$, $K=0.090$ for the reaction $$\ce{H2O (g) + Cl2O (g) -> 2HOCl (g)}$$ calculate the concentrations of all species at equilibrium for the case: $\pu{1.0 g} \ce{H2O}$ and $\pu{2....
5
votes
2answers
829 views

How much electricity could be generated by a person's stomach acid?

Motorola has a device that is powered by stomach acid. Given that a battery consumes the electrolyte as it generates a charge, how much power could be generated using a device such as this? Let's ...
4
votes
1answer
113 views

Are these two reactions equivalent?

I'm supposed to balance a redox equation. I arrive at $$ \ce{H2O} + \ce{NH4+} + 2\ce{S^{2-}} + \ce{O2} \rightarrow \ce{NH3} + 2\ce{S} + 3\ce{OH-} $$ The "official" solution is $$ 4 \ce{NH4+} + 2\ce{...
1
vote
1answer
620 views

Wasn't Rutherford's assumption of gold foil to be made of single layer wrong?

My teacher taught about Rutherford's gold foil experiment today. Sir said that, Rutherford used gold foil of thickness $10^{-7}$ m and concluded atom to be of size $10^{-10}$ m. Sir also said that ...
11
votes
3answers
11k views

Why is Potassium in French and English not called Kalium?

The symbol from the periodic table for Potassium is "K". This fits my native language (dutch), where Potassium is called "Kalium". The same question applies to Sodium (Na), which again in Dutch is ...
2
votes
0answers
105 views

Isoelectric point pH, mV, for a metal oxide nanopowder

I'm trying to make a solution of $\ce{TiO2}$ that will coat stuff in as dense a monolayer as possible. To do so, I'm using nano sized $\ce{TiO}$ particles and trying to get them to get as close to ...
1
vote
1answer
2k views

Corrosion of Aluminum by Baking soda

An aqueous solution of sodium hydrogen carbonate corrodes aluminum foil quite readily. How do you explain this?
3
votes
1answer
10k views

Making ice from carbonated water

Sorry if this is not the place for asking this question, but I'm going to do a real life project and don't know where else to ask. I'm going to prepare and sell snow cones next summer. For making ...
16
votes
4answers
27k views

Ozonolysis conditions for benzene

What are the precise conditions under which benzene undergoes ozonolysis? All anyone can tell me is that it undergoes ozonolysis under "vigorous" conditions. But, what vigorous conditions?
19
votes
2answers
5k views

What is the edge of a diamond like?

The chemical structure of a diamond is defined as an endless lattice in which each carbon atom is covalently bonded to four other carbon atoms situated at the four ends of a tetrahedron. But of ...
5
votes
1answer
6k views

Selectivity in aldol condensation between pivaldehyde and acetone

In a crossed aldol condensation (condensation between aldehyde and a ketone), the primary products are such, that the carbonyl group of the ketone remains intact, and the $\alpha$-hydrogen of ketone ...
2
votes
1answer
784 views

What is the reason behind the characteristic colors of elements?

I've been trying to find out about this for some time now and when I searched online, I couldn't get any solid reasons. My question is: What is the reason for the characteristic colors of elements? ...
9
votes
2answers
61k views

Isothermal vs. adiabatic compression of gas in terms of required energy

I am working on an instruction manual of sorts to be used with an introductory course in thermodynamics. As an example of problem solving, I attempt to answer the following question: If you have ...
1
vote
1answer
670 views

If I add some KOH, where will the reaction shifts?

I just got a final test and one of the question is: $\ce {Ni^2+}$ + 6$\ce{NH_3}$ $\ce {<=>}$ $\ce{[Ni(NH3)6]^2+}$ If we add some aqueous $\ce{KOH}$ after the reaction reach equilibrium, where ...
4
votes
1answer
1k views

Is there any substance that's a 0-0-0 on the NFPA diamond?

Is there any substance that's a 0-0-0 on the NFPA diamond? Basically a perfectly safe chemical.
1
vote
1answer
92 views

Red glow in the dark pigments

I want to do some spectrometry experiments with glow in the dark paints. The red paints I've read product details for all seem to require a uv light to charge. Are there any red glow in the dark ...

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