All Questions
Tagged with aqueous-solution analytical-chemistry
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Effects of Ka on the Half-Equivalence Point
I'm new to studying chemistry at a university level and am currently reviewing acid-base titrations. I am wondering about the relationship between your ionization constant for a weak acid ($K_\mathrm{...
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Qualitative analysis of iron(III) salt
Why will $\ce{Fe^3+}$ give brown ring test?
In my textbook it was given that ferric ion gives brown ring too. I am confused, if ferric ion is already present, then what will reduce nitrate ion to ...
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Calculating solubility of iron(III) hydroxide in water
The following example in Skoog's Analytical Chemistry uses mass-balance and charge-balance equations to calculate the solubility of iron(III) hydroxide in aqueous solution.
$$
\begin{align}
\ce{Fe(...
- 811
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What causes the turbidity when preparing Fenton's reagent?
New guy, please be gentle. I might ask questions not according to conventions, I am not a chemist nor do I study chemistry. Feel free to adapt the question and the tagging.
I am preparing a solution ...
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Potentiometric determination of fluoride
We did an experiment of potentiometric determination of fluoride ions. In several beakers we added several concentrations of NaF solutions and then we added water. We calculated with the electrode the ...
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How much additional hydrochloric acid should be added to arrive at ‘excess acid’?
I am an IB student. And I am trying to find the mass percentage of $\ce{NaHCO3}$ in antacid. I am dissolving the antacid in $\pu{0.1 M}$ $\ce{HCl}$ solution. So, first of all I conducted some ...
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How do I measure out these salts using the proper method?
I'm planning on preparing a water solution using the following salts of reagent grade with approximately these concentrations:
\begin{array}{lr}
\ce{CaCl2} & \pu{10 mg/L}\\
\ce{Na2SO4} & \...
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Where is my antimony going?
I work in a trace metals laboratory operating an ICP-OES. I've been having some trouble with the recovery of antimony in a weak $\ce{HCl}$ solution post-digestion.
The antimony is part of a mix of ...
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pH probe bulb - what is happening within the glass?
I am trying to understand how the glass bulb of a pH electrode of a pH meter works - the glass bulb itself. Not the reference electrode or the rest of the electrode (HCl, Ag/AgCl wire, etc...), the ...
- 5,900
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Reaction of sodium hydroxide with ethanol
I am carrying out a titration to determine the solubility of a carboxylic acid in mixtures of water and ethanol. I will be titrating a diluted (previously) saturated solution of water, ethanol and the ...
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How would I measure the dissolved carbon dioxide content of a liquid (water to start with)
I would like to measure the dissolved carbon dioxide content of a sample of water. I was thinking that conductivity might change with carbon dioxide level, and also pH. I would like to have the ...
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Why does the composition of Ocean Water list sodium and chloride separately?
This is the site I am using.
It is also found here, but this uses mg/L instead of percents.
It lists Sodium at 30.8%, and Chloride at 55.3%. How can this be? Shouldn't the two be listed as Sodium ...
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Do I need to include calcium chloride in this reaction equation?
Yesterday I titrated a solution of calcium hydroxide in aqueous calcium chloride with $16.7~\mathrm{mL}$ of $\ce{HCl}$. More specifically, I took $25\ \mathrm{mL}$ of the calcium hydroxide in aq ...
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Why does Devarda's alloy include copper?
Devarda's alloy is used in the detection of nitrates. However, judging by the reaction equation, only aluminium plays the role of reducer:
$$\ce{3NaNO3 + 8Al + 5NaOH + 18H2O -> 8Na[Al(OH)4] + 3NH3(...
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Calcium sulfate soluble in water
In the volumetric estimation of calcium in a given solution as calcium oxalate. We convert the calcium oxalate to oxalic acid by dissolving the former in hot (~70 °C) 2 N sulfuric acid solution. This ...
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