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How to calculate bicarbonate and carbonate from total alkalinity [closed]

It's been a long time since I did my chemistry classes and I'm currently trying to analyze groundwater samples for hydrogeology purposes. I would like to evaluate carbonate and bicarbonate ...
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1answer
87 views

Controlling Current Density in Electrowinning Cell

What are the parameters which govern the current density in an electrowinning cell? What equations relate Current Density to the applied potential difference? Is it simply just Ohm’s Law J = σE? ...
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2answers
20k views

How does the polarity of the eluent and sample affect the Rf value in thin layer chromatography?

A three-component mixture (X, Y, Z) was separated using normal phase TLC. Three eluents of varying polarity were used. Select the TLC plate that was developed using the least polar eluent (click on ...
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1answer
2k views

Incense Stick vs Candle

*Not sure whether to put this on Phy or chem.. * What exactly happens when you light an incense stick? How is this different from a candle, or embers for that matter? From what I understand, a ...
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2answers
2k views

How to calculate the amount of substances product produces from the masses and amounts of starting materials?

Calculate the amount of carbon dioxide formed when we burn 1 mole of carbon in the presence of 16 g of dioxygen. $$\ce{C + O2 -> CO2}$$ 1 mole of carbon means 12 g. Therefore amount of ...
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1answer
3k views

Can CH3COOH be written as C2H4O2? [duplicate]

I was reading a chapter on acids and bases .It said something about acetic acid.And then I thought whether I could write CH3COOH as C2H4O2? please explain your answer. Thanks!!
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0answers
45 views

pH responsive polymer which is immiscible in water?

Can anyone suggest a pH-responsive polymer, which is immiscible in water (polar solvent) but miscible in oil (e.g vegetable oil)? I want to study the change in the density of such polymers when they ...
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1answer
1k views

How do I calculate the enthalpy change when a gas is being used to heat water?

The question I'm trying to answer is: Calculate the mass of butane gas that would be needed to heat $724\ \mathrm{cm^3}$ of water from an initial temperature of $7.44\ \mathrm{^\circ C}$ to $50.7\ \...
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1answer
712 views

Why is iron pentacarbonyl known, but iron(III) hexacarbonyl is not?

Why is the neutral complex $\ce{[Fe(CO)5]}$ known, but the cationic carbonyl complex $\ce{[Fe(CO)6]^3+}$ is not known?
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1answer
13k views

Why is FeCl3 covalent? [duplicate]

There is an electronegativity difference of 1.2 between $\ce{Fe}$ and $\ce{Cl}$. Then why it is covalent?
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2answers
239 views

Which resonance structure would be favorably contributed to the actual structure?

Total number of pairs of resonating structure in which second is more favorable than first: I know (d) and (e) have second structure more stable. (f) has both same. According me to, (a) and (c) ...
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0answers
31 views

How can the torsional barrier of a polymer determined by molecular dynamics?

First consider a simple polymer, like polyacetylene: Its torsional barrier can be determined by DFT calculations by considering "enough" units and performing a simple dihedral scan. "Enough" appears ...
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2answers
1k views

Salinic bridges in voltaic cells

I'm doing a study a study on voltaic cells. I've been working with them for a while and one of the questions that I've had is how does the salt bridge affect the cell. I mean, I know it allows ions to ...
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1answer
5k views

Why is AlCl₃ is known as aluminium chloride while PCl₃ is known as phosphorus trichloride? [duplicate]

Why is $\ce{AlCl3}$ is known as aluminium chloride while $\ce{PCl3}$ is known as phosphorus trichloride? I think it is due to variable valency if phosphorus. Is it true?
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1answer
140 views

Distinguishing between potassium chloride and sodium chloride

I have these very large blocks of salt intended for a water softener in my house, but I'm not sure if they're potassium chloride or sodium chloride, according to what I've read they're both widely ...
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1answer
2k views

What is meant by “fairly” when used as a quantifier for the solubility of a chemical?

While doing homework and I found a statement that says a chemical is fairly soluble in water, but I do not understand what this means. However, I know that when things are soluble in water they tend ...
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2answers
4k views

Structure of the bifluoride anion [duplicate]

I came across this structure of $\ce{HF2-}$ and realized that the bond shown between H and F is a hydrogen bond. $$\Large\ce{[F-H-F]-}$$ HF hydrogen bond are the strongest hydrogen bonds we know, ...
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1answer
10k views

What is the mechanism for the oxidation of benzene to maleic anhydride using vanadium pentoxide? [closed]

What is the mechanism for the oxidation of benzene to maleic anhydride using vanadium pentoxide, $\ce{V2O5}$?
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1answer
325 views

Stereochemistry of cycloalkanes having substituents

My teacher said that from $3$ to $6$ member cycloalkanes having any number and type of substituents we can always draw the planar structure and decide the specifics of stereochemistry like: ...
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3answers
99 views

Indicator for H2S [closed]

In there an indicator for sulfur compounds like H2S (also organic)? Or some straight forward way to measure if the H2S concentration in the air is higher than usual? Or is the concentration too low ...
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0answers
41 views

Reference for Hammett acidities of dilute H2SO4?

When $\ce{H2SO4}$ is dissolved in water in little amounts ($<\pu{1M}$), the $\mathrm{pH}$ scale can be used to measure the acidity of the solution. However, in larger concentrations, this breaks ...
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2answers
183 views

Comparison of boiling points

I was comparing boiling points of $\ce{CHCl_3}$ and $\ce{CH_3Cl}$. According to me B.P. of $\ce{CHCl_3}$ should be higher due to it's higher molecular mass than $\ce{CH_3Cl}$, but the answer is ...
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2answers
409 views

Why does a distinction between homogenous and heterogenous mixtures exist?

Take a known homogeneous mixture like air (oxygen and nitrogen) for example. The two have different atomic masses, so the molecular weight is different. If I let the solution sit there for a long time,...
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1answer
620 views

Fischer's proof of the structure of glucose

To differentiate between Mannose and Glucose , Fischer developed a series of reactions to make the aldehyde group to alcohol and terminal alcohol to aldehyde. What was this series of reactions ? Even ...
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6answers
6k views

Why convert to moles for stoichiometry calculations? [closed]

Why do you have to convert the reactants and products of an equation to moles when doing stoichiometry problems? Why can't you just convert straight to grams to solve the problem?
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2answers
66 views

Why is the ionic product of water $K_w$ the same in acid, water, and alkali? [duplicate]

Seen on the web: The concentration of [H+] and [OH−] both vary based on the the composition (acid/alkaline) of the solution, but the remarkable thing is that their product does not. When [H+] goes ...
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1answer
1k views

Why does increasing the concentration of the salt bridge in a galvanic/voltaic cell increase voltage?

I recently set up an experiment with 1M half cells made up of zinc and copper nitrate. They were connected with a sodium nitrate salt bridge of varying concentrations. As the concentration doubled 5 ...
-1
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2answers
2k views

Understanding the bond-line representation of glycine

I'm confused because I see now two different way to represent the glycine amino acid. while I understand the first way of the representation the second one I don't understand at all. I believe that ...
-1
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1answer
2k views

Iodate ion and Octet rule

'm trying to figure out why the oxidation state of the iodate ion is +5. The iodine atom has 7 electrons in its outermost shell (comprised of s and p sub-shells). Two oxygen atoms receive 2 electrons ...
-1
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2answers
57 views

How does the value of the equilibrium constant give information about the extent of reaction at equilibrium?

Pretty much everywhere I've read, the numerical value of the equilibrium constant gives you information about the relative concentrations of products and reactants in the equilibrium mixture; the ...
-1
votes
2answers
3k views

Why does vinegar and baking soda yield a far smaller volume of carbon dioxide gas than expected from calculation?

I experimented $\ce{CO2}$ generation by adding $\pu{4 g}$ of $25\%$ acetic acid water solution ($= \pu{1 g}$ of acetic acid) to $\pu{1.4 g}$ of pure baking soda. But this mixture yielded only $50\%$ ...
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2answers
7k views

Is there a chemical that when added to water makes the water flash evaporate?

Im wondering if there is a chemical that you can add to water that will make it evaporate extremely fast, either by raising the temperature of the mix or some other method.
-1
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1answer
860 views

Is sodium hypochlorite 100% concentrate possible?

Popular bleaching brands like Clorox contain liquid sodium hypochlorite in small concentrations, ranging from 5-12.5% (is this a mass/volume, mass/mass, or volume/volume concentrate?). Is it possible ...
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2answers
30k views

Why is O2 enough to form a mole of Oxygen? [closed]

I understand that this is the most basic knowledge of moles, however I'm still unsure - according to easy research, $\ce{O2}$ forms a mole of Oxygen. As a mole is $6.022*10^{23}$, exactly what on the ...
-1
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1answer
163 views

Help regarding stereochemically inactive s orbital [duplicate]

Author JD Lee says in his book, Inorganic Chemistry The dipole moment of $\ce{XeF6}$ is approximately = $0$ because the lone pair is present in the stereochemically inactive s orbital. What is ...
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1answer
2k views

How to calculate the equivalent mass of Na2S2O3? [closed]

Let us consider the following reaction $$\ce{I2 + 2 Na2S2O3 -> 2 NaI + Na2S4O6}$$ Now, in order to calculate the equivalent mass of $\ce{Na2S2O3}$, first I need to calculate it's $n$-factor which ...
-1
votes
2answers
1k views

Can we rotate a mirror image by any angle to check if it is superimposable? [closed]

A molecule is chiral when it is different from its mirror image, and achiral if it is identical to its mirror image. To check if the mirror image is identical to the original object, we have to check ...
-1
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1answer
240 views

Why does a strong acid displace salt of weak acid? [closed]

This thing has been bugging me for a few days. I don't understand why a strong acid displaces a weak acid from it's salt solution.
-1
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1answer
53 views

Ratio of carbon monoxide and carbon dioxide when carbon and oxygen are made to react [duplicate]

$\pu{12 g}$ of $\ce{C}$ reacts with $\pu{64 g}$ of $\ce{O2}$ to give a mixture of $\ce{CO}$ and $\ce{CO2}$. Find amount of $\ce{CO}$ and $\ce{CO2}$ at the end of reaction. What I tried was to let x ...
-1
votes
1answer
3k views

How does a change in the surface area of the electrodes affect the voltage produced by a galvanic cell?

I did a lab where I increased the surface area of the electrodes in a galvanic cell, that resulted in an increase in voltage. However, I have been reading and that is not supposed to happen. I am a ...
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1answer
1k views

Questions on Neutral oxides

Neutral oxides, are non metal oxides which are neither acidic nor basic. I have noticed a pattern for neutral oxides which I am unsure actually holds true. $\ce{CO}$, $\ce{H2O}$, $\ce{NO}$ and $\ce{...
-1
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1answer
188 views

The Definition of a Solution

Can there be more than one solute or solvent in a solution. Why? Why not? The largest component in the solution is called a solute and smallest a solvent. How is this possible when solutions contain ...
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1answer
3k views

Why is the combustion of Nitrogen endothermic? [closed]

Other combustion reactions are exothermic but this combustion reaction endothermic. Why ? Please explain..
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1answer
482 views

Is there any type of liquid, other than mercury, that PTFE teflon is known to “float” to the surface in?

The specific gravity of PTFE teflon is roughly 2.3. I have a 3/8" diameter sphere made up of entirely PTFE teflon, and I would like for it to float to the surface when dropped into a liquid. Does ...
-1
votes
2answers
8k views

What is the IUPAC name of [Cr(H2O)5Cl]Cl2.H2O [closed]

What is the IUPAC name of $\ce{[Cr(H2O)5Cl]Cl2.H2O}$? The net says that the correct name is Pentaaquachloridochromium(III) chloride. But do we not have to account for the water molecule present ...
-1
votes
1answer
97 views

How is equilibrium achieved in osmosis?

According to BRS Physiology book: excessive NaCl intake will lead to an increase in the osmolarity of the Extracellular Fluid (ECF) compartment, and thus will lead to water shift from the ...
-1
votes
2answers
143 views

Is there a quick way to approximate a logarithm in Nernst equation?

The problem is as follows: In a galvanic cell the cathode is an $Ag^{+}(1.00\,M)/Ag_{(s)}$ half-cell. The anode is a standard hydrogen electrode immersed in a buffer solution containing $0.10\,...
-1
votes
1answer
209 views

Why is 1,2-diiodoethane unstable? [duplicate]

Diiodoethane is a product of the reaction between glycol and $\ce{PI3}$. Why is 1,2-diiodoethane unstable?
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3answers
100 views

Confusion on ion product of water

The ion product of water is defined as $$ K_w = [\ce{H+}][\ce{OH-}] $$ and in pure water $ [\ce{H+}] = [\ce{OH-}]= 1.0 \times 10^{-7}$ and $ K_w = 1.0 \times 10^{-14}$. It is said that if we dissolve ...
-1
votes
2answers
208 views

What type of chemical reaction is this?

So far we have learned about about single displacement, double displacement, gas evolving, neutralization, synthesis, disassociation, and combustion. I was trying to solve the following chemical ...

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