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Why is methoxide a strong base?

Why is methoxide strong base? In case of halogens, I get why one is weak base, and one is strong base, but in the case of ones with oxygen, this seems to be hard to figure out.
5
votes
5answers
5k views

Can natural gas appliances run on Hydrogen?

Can natural gas appliances run on Hydrogen? If so, does the appliance have to be modified and how significant of a modification would it need? Thanks
2
votes
2answers
1k views

How many elements in food?

A slightly deranged curiosity: if we had a 3D printer able to “print” anything starting from “cartridges” of pure chemical elements, how many of the 118+ possible cartridges (or of the 98ish for non-...
2
votes
0answers
430 views

Analysis of a mixture of carbonate salts

We've got a mixture of carbonate salts. It's a buffer, used in fish tanks. How might we go about identifying the components and their concentrations? I suspect it'd be hard to separate some of this. ...
10
votes
4answers
113k views

Is melting/boiling point of ionically bonded substance higher than of covalently bound?

Is the melting and boiling point of ionic bond usually higher than covalent bond? I know that compounds with ionic bonds are usually solid at room temperature, so I want other answers than this. (...
-1
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2answers
11k views

Energy required to break single bond vs double bond vs triple bond of a carbon atom in an organic molecule

Assuming every other conditions are the same, what would be the comparison of energy required to break single bond, double bond and triple bond of a carbon atom in an organic molecule?
4
votes
3answers
10k views

How do indicators work when they mixed with each other?

Methyl orange, bromothymol blue and phenolphthalein indicators were mixed together to form a solution. Over what pH range would the solution be yellow? I cannot understand the question. If two or ...
7
votes
2answers
25k views

Why is ethanol written as C2H5OH not C2H6O?

This is balanced equation of fermentation of glucose: $$\ce{C6H12O6(aq) -> 2C2H5OH(aq) + 2CO2(g)}$$ I know that the result of glucose fermentation is ethanol ($\ce{C2H6O}$). What represented in ...
1
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2answers
3k views

Why does a silane group react with hydroxyl groups?

I read somewhere that a silane group will react with hydroxyl groups. Does anyone know why this would happen?
1
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2answers
8k views

What impact does heating or cooling have on the oxidation reduction potential of water?

There are alkalinizing water ionizers on the market that lower the ORP of water. Does heating or cooling that water have an impact on its ORP?
4
votes
2answers
3k views

How do you explain the thread sticking to an ice-cube when salt is sprinkled over it?

So this experiment goes like this : You take an ice-cube You put a thread on top face of it You sprinkle some common salt on the ice-cube wherever its touching the thread You wait for sometime (...
8
votes
3answers
190k views

How can melting point equal freezing point?

I don't understand how the freezing point of a substance is the same temperature as the melting point of the same substance. For example, if liquid water freezes at 0 °C how can ice also melts at 0 °...
5
votes
1answer
13k views

What is the effect of adding salt to ice?

What will happen to the melting point temperature of ice if some common salt is added to it? How to justfy the answer?
6
votes
1answer
732 views

Having problems running DFTB using dftb.org parameter files on Gauss 09 (G09)?

I ran into an issue trying to run dftb.org parameter files on G09 and found questions asked on this but not answers. I thought I would post the solution here to help anyone else who may run into this ...
22
votes
1answer
463 views

Molecular Imaging - Any surprises to be had?

Molecular imaging, using STM and AFM technologies, appear so far to visually prove most of what we already know about chemical structures, such as VSEPR theory. For instance, here are the ideal ...
10
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3answers
2k views

Why is tantalum so unreactive?

What is the fundamental argument behind explaining why Ta metal is so inert and does not usually participate in corrosion? I know that it forms a protective oxide, but nothing explains why in an ...
6
votes
1answer
30k views

Effect of dillution on titration

When we are titrating acid/base using ph meter we add distilled water to immerse the ph electrode. Won't this affect the concentration of the acid/base: I mean isn't this dillution. Won't this ...
5
votes
4answers
16k views

Are fractional oxidation states possible?

To get the oxidation state of carbon (denoted $x$) in octane, $\ce{C8H18}$, I used the fact that hydrogen has an oxidation state of $+1$: $$8x + 18\cdot 1 = 0 \qquad \Longrightarrow \qquad x = -\frac{...
4
votes
2answers
2k views

Chemical Equilibrium - Why does changing the temperature shift the equilibrium?

I know that raising the temperature in a reversible chemical reaction causes the equilibrium to shift to the endothermic side. I know that $\Delta G = \Delta H − T\Delta S $ but I don't know how to ...
6
votes
3answers
3k views

How can I measure the pH of high-viscosity fluids like dough?

I would like to measure the pH value of dough with a pH-Meter, to ensure a pH value of 4.1 (max). Because of the high viscosity I would thin down the dough with demineralized water for two reasons: I ...
1
vote
0answers
38 views

Chemical Equilibrium - Why does changing the temperature shift the equilibrium? [duplicate]

I know that raising the temperature in a reversible chemical reaction causes the equilibrium to shift to the endothermic side. I know that $\Delta G = \Delta H - T \Delta S$ but I don't know how to ...
5
votes
3answers
3k views

Why do you need a strong base for a titration

For a titration, if you want to know the concentration of an acid you use a strong base such as $\ce{NaOH}$. My question is; why you can't use a weak base for this purpose? Is it because the ...
7
votes
1answer
163 views

Interpretation of Figure - biofunctionalization

In this paper on page 1985 they say: Fluorescence analysis confirmed that enhanced protein binding at higher electron dose depends only to a small extent on the slight increase in the lateral ...
4
votes
0answers
276 views

What is the average chain length of a glutaraldehyde crosslink between primary amines?

Imagine I'm performing a primary amine to primary amine (i.e. PA to PA) crosslinking reaction at $37~^{\circ}\mathrm{C}$ in phosphate-buffered saline (pH $\approx 7.4$) with glutaraldehyde drawn from ...
2
votes
1answer
119 views

How are arsenic compounds removed from drinking water?

I used to live near a volcano where the groundwater contains naturally occurring arsenic compound. Since $\ce{As2O3}$, $\ce{As2S3}$, and $\ce{As4S4}$ are predominantly occurring in drinking water, ...
2
votes
1answer
170 views

How to solve this contradiction?

I am getting confused about this the more problems I do on it. My understanding was that only strong acids and strong bases will react to produce water and a salt. Something like this: Molecular Eq: $\...
-1
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2answers
1k views

Which ions do not react with each other in a solution? [closed]

Which ions do not react with each other in solution? A. $Ba^{2+},SO_4^{2-},NO_3^-$ B. $Cu^{2+},SO_4^{2-},OH^-$ C. $Ag^+,Cl^-,H^+$ D. $K^+,Fe^{3+},Br^-$ I have no idea why the answer is D. Please help....
1
vote
1answer
4k views

Vapour pressure varing with molality

Vapour pressure of water at 298 K is 0.025bar. Following solutions are prepared at the given temperature whose molality I have calculated to be, Solution A 0.56m urea dissolved in 178.2g of water ...
6
votes
2answers
4k views

Geometrical isomerism in cycloalkenes

Why doesn't cyclohexene have a cis-trans isomer whereas cyclodecene has one? Is strain a factor?
1
vote
1answer
2k views

is it possible to store formic acid longer if frozen?

I would like to know if formic acid (concentrated to 85%) is stable (no chemical reaction) when frozen. Is it a good solution to store it for many years?
10
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2answers
2k views

Why is the mole a unit of measurement?

I really can't understand why is the mole a unit of measurement and not just a constant. I mean, we use units to express things that we can measure but that are not countable, that are continuous - ...
2
votes
1answer
260 views

Does single-layered Aluminium Phosphide exist?

I'm currently working with the band structure of graphene and graphene-like compounds. α-Boron Nitride (hexagonal, single layer) has many interesting properties. I was wondering if the next period ...
4
votes
2answers
1k views

How to chemically postpone a chemical reaction

This question is about delaying/postponing chemical reactions in general, but I will explain my point based on an example. Most of you will know the famous vinegar and baking soda experiment which ...
31
votes
1answer
19k views

Why does the unstabilised Wittig reaction selectively form cis alkenes?

This question is meant for a simple unstabilised ylide. The mechanism of the Wittig reaction, as given on ChemTube3d, involves a concerted formation of the oxaphosphetane (this is generally favoured ...
4
votes
2answers
2k views

Cathodic protection of aluminium

I am planning an experiment for a chemistry class about corrosion. I am going to show how different prevention methods affects the corrosion of iron and aluminium parts using bleach as the oxidizer. ...
1
vote
2answers
10k views

Which one is nitric Acid, HNO3 by itself, or when it is included in H2O?

This is a quote from my Chemistry textbook: Nitric acid ionises according to the following equation: $$\ce{HNO3(l) + H2O(l) -> H3O+(aq) + NO3- (aq)}$$ I know that the formula for nitric acid ...
19
votes
1answer
9k views

Why are the halogens good disinfectants?

I've been searching around the internet for a while and I know that Chlorine, Bromine and Iodine are used as disinfectants. My question is, what is the property of the halogens that make them ...
9
votes
4answers
83k views

What is the condensation point of water?

The boiling point of water is $\pu{100^\circ C}$. However, we find that even at room temperature, water can evaporate into gas. Therefore, water vapor can exist at temperatures of, say, $\pu{50^\circ ...
2
votes
1answer
10k views

Identifying Reaction Types

I need help on identifying precipitation, acid-base, and redox reactions. I know what each one is in theory: Precipitation: Creating a solid Acid-Base: neutralization Redox: exchange of electrons ...
8
votes
3answers
11k views

Esterification of a carboxylic acid and the production of water

In an esterification reaction between a carboxylic acid and an alcohol, a carboxylate ester and water is produced. I found the following diagram online, and my textbook has a similar one as well ...
4
votes
2answers
1k views

A few questions about the conditions of the Diels Alder Reactions

I'm attempting to extract the diels alder reaction into a generic reaction and am trying to gain a better understanding of it. Can a conjugated diene react with another conjugated diene via the diels ...
0
votes
2answers
267 views

Crystallization from a solution

I was wondering if there is any other way to crystallize materials from a solution other than using supersaturation? Thanks,
3
votes
1answer
810 views

Parts of a manometer

There is a poor quality photo in the diagram of a manometer below: The picture is too poor for me to understand what they mean by "glass pointer marks calibrated volume". I would be interested if ...
5
votes
1answer
4k views

What is the substance in the new water cooler filter that give bubbles and taste a bit like soap

Recently the water cooler was replace with a new filter. However, when I refill my water kettle with the water from the water cooler, there are many bubbles and the taste was a bit like soap. What ...
3
votes
1answer
1k views

Forms of Henry's law versus ideal gas law

This might be a slightly daft question as I'm a physicist rather than a chemist, but I have a slight problem in using Henry's law which I think I can circumvent using the ideal gas law – I'd be ...
0
votes
2answers
7k views

How does the volume of a mole of ideal gas relate to pressure and temperature?

The volume of a mole of gas is: $\ce{22.4 l}$ directly proportional to pressure and Kelvin temperature. directly proportional to pressure, inversely proportional to Kelvin temperature. inversely ...
-3
votes
1answer
714 views

Why can't you see air but can feel it [closed]

Is there a device that can measure the air in the room in lbs? I would appreciate the anseer
8
votes
4answers
25k views

Why won't water freeze if you put ice in it, despite ice being frozen?

Just now I got some room temperature water and added some ice to cool it, and it just came to me, like the scientist I wish I was ... why doesn't frozen (freezing point) ice added to higher ...
5
votes
3answers
254 views

Can I perform a stable isotope analysis at home?

I'm interested in measuring the stable isotope ratios of some bird feathers. I'm aware that a mass spectrometer is required to measure stable isotope ratios. Is it possible to measure stable isotope ...
5
votes
3answers
14k views

Are there substances that cannot undergo combustion?

Are there substances that cannot undergo combustion? If so, what are they?

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