Unanswered Questions
319 questions with no upvoted or accepted answers
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Mass of boron in boric acid
I have recently submitted a slime activator product for EN71-3 UK toy safety testing. The test aims to measure the amount of boron that is able to migrate from the toy if it is consumed by a child in ...
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Why DMSO has much higher freezing point than DMF (19 °C vs -61 °C)?
Recently, while solvent optimization of a reaction, I found DMSO froze in an ice-bath but DMF didn't.
From Wikipedia, I found out that DMSO (dimethyl sulfoxide) has a freezing point of 19 °C (ref. 1) ...
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Can a diamond dissolve in molten iron?
The melting point of diamond is 4000C and the melting point of iron is 1538C. However, the question is if a diamond is soluble in an iron solvent. Diamond is made up of carbons. And I know steel is ...
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Experiment on pH vs Rate of Electrolysis - what do the results actually say?
My experimental setup looks at using different pH solutions (of $\ce{H2SO4}$ and $\ce{NaOH}$) for electrolysis of water with a Hoffman setup and then measuring the rate of production of gas (note this ...
CommunityBot
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How to dissolve a powdered drug once it has been mixed with water
For a biological experiment I have acquired $\pu{10 mg}$ of CHIR 99021 (laduviglusib). In order to obtain a $\pu{10 mM}$ stock solution, I had to dissolve the powder in $\pu{2.15 mL}$ of dimethyl ...
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Salts solubility and speciation calculations using PHREEQC
I am collecting data from literature for CO2 solubility in aqueous solutions. These are usually synthetic brines and are reported as molalities or wt% of salts or salt mixtures (I have NaCl, KCl, ...
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Secondary alkyl halides and strong base: Sn2 vs E2
I got this question from the PYQs of a college entrance exam. According to the answer key, 4-chloro-3-methylpent-1-ene reacts with NaOH in water to give 4-hydroxy-3-methylpent-1-ene via the SN2 ...
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Who is more polar: acetonitrile or methanol?
According to data dipole moment of acetonitrile is around 4 while that of methanol is 1.7 but is said that acetonitrile is more soluble in non polar solvent that methanol.
But shouldn't methanol be ...
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Stability of n-Dodecyl-beta-D-maltoside in buffer solutions for assay experiments
I have a buffer system which contains multiple salts and in addition DTT and n-Dodecyl-beta-D-maltoside.
I understand that DTT is hydrolysing quite fast and this component must be used always fresh ...
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Estimation methods for temperature evolution of a high $\Delta H_{mix}$ dilution ($\ce{KOH}$ in water)
Question up front: Can temperature evolution in solutions be short-hand-estimated by simple state based calculations - with reasonable expectations of precision? (+/- 10° C)
I am trying to calculate ...
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What does it mean for a substance to be "sparingly soluble"?
I have trouble understanding what solubility means. Merriam-Webster defines it as follows:
1 the quality or state of being soluble
2 the amount of a substance that will dissolve in a given amount of ...
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Increasing energy density for flow batteries with water based electrolyte?
Given a flow battery with a water based electrolyte, would it be possible to increase the energy density of battery by precipitating the redox active species from the anolyte and catholyte solutions? ...
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Freezing of a beverage
I am trying to generally describe the process of freezing beer and how the different ingredients influence the freezing process. My general approach right now is to observe a beer as 90% water and 10% ...
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Mass of gaseous ammonia required to prepare ammonia solution of a given pH
How many grams of gaseous ammonia do you need to make $\pu{200 mL}$ aqueous ammonia solution with $\mathrm{pH} = 11.34?$
As the mole ratio is the same for $\ce{H+}$ and $\ce{NH3},$
$$\ce{NH3 + H+ -&...
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visualization problem of dilution of enthalpy $\Delta_{dil} H$ data with different initial concentrations
description
I have a question about the $m_f$ vs. $\Delta_{\text{dil}} H$ plot in some experimental studies.
For example, the dilution-of-enthalpy data at 300 °C with two initial concetration ($m_i$) ...
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