Why Didn't Last 2 Test Tubes Dissolve?

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SUMMARY

The discussion centers on the solubility of benzoic acid in various solvents, specifically focusing on why the last two test tubes containing NaHCO3 and diethyl ether did not dissolve the acid. Strong bases like NH4OH and NaOH effectively neutralize benzoic acid due to their higher basic dissociation constants (K_B), with NH4OH at 1.8·10^{-5} and NaHCO3 at 2.3·10^{-8}, indicating that NaHCO3 is approximately 1000 times less basic than ammonia. The solubility of benzoic acid is also influenced by its polar nature, which allows it to dissolve in polar solvents like water and acetone, but not in non-polar solvents such as diethyl ether.

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  • Understanding of acid-base chemistry, specifically the concept of dissociation constants.
  • Knowledge of solubility principles, particularly "like dissolves like".
  • Familiarity with polar and non-polar solvents.
  • Basic knowledge of chemical compounds, specifically benzoic acid and its properties.
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  • Research the solubility rules for organic compounds in various solvents.
  • Study the dissociation constants of other common acids and bases.
  • Learn about the properties and applications of ammonium hydroxide in chemical reactions.
  • Explore the differences between polar and non-polar solvents in chemical processes.
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Chemistry students, laboratory technicians, and anyone interested in the solubility behavior of organic acids and their interactions with various bases and solvents.

MeatyDumplings
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i have 5 test tubes with benzoic acid, and i pour NH4OH, NaOH, HCl, NaHCO3 and diethyl ether into different tubes. The first 3 dissolved completely but the last 2 did not. Any ideas why?
i don't believe "like dissolves like" applies here since they are all polar.
 
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I would be curious about how the basic dissociation constant of NaHCO3 compares to that of NH4OH. Check the handbook information. I'm not sure at the moment why the bicarbonate ion would not neutralize the benzoic acid; benzoic acid itself may be too weak an acid to add a proton to the bicarbonate ion. The Ammonia (solution in water) and the NaOH are both strong enough bases to neutralize the benzoic acid; and generally, Na+ salts and ammonium salts are soluble.
 
K_B(NH_4OH) = 1.8\cdot10^{-5}

K_B(HCO_3^-) = 2.3\cdot10^{-8}

So NaHCO3 is about 1000 times less basic than ammonia.
Benzoic acid is a solid made of polar molecules, so it dissolves quite well in polar solvents as water and acetone and not in non-polar as diethyl ether.
 
I came.across a headline and read some of the article, so I was curious. Scientists discover that gold is a 'reactive metal' by accidentally creating a new material in the lab https://www.earth.com/news/discovery-that-gold-is-reactive-metal-by-creating-gold-hydride-in-lab-experiment/ From SLAC - A SLAC team unexpectedly formed gold hydride in an experiment that could pave the way for studying materials under extreme conditions like those found inside certain planets and stars undergoing...

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