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Why is it that every snowflake is unique?

It turns out that 2 identical snowflakes have been observed, but... Two Identical Snowflakes Although when we think "snowflake" we usually picture an object with 6-fold radial symmetry, snowflakes ...
• 82.5k
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Reaction of silver nitrate and hydrochloric acid

One of the most difficult parts of chemistry is learning to recognize a type of reaction based solely on its reactants. This has to be done before you can apply a reaction pattern to the problem, and ...
• 10.1k
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Why exactly does precipitation occur?

Short story Maybe it will help to think first about a ridiculous case. Say you have a large hydrophilic solid, and a small drop of water is added on top. We would not expect the entire solid to ...
• 6,871
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Are precipitations exothermic and/or endothermic?

No, absolutely not. Precipitation reactions can be either endothermic and exothermic. Table 1. Thermodynamic data of precipitation for some salts \begin{array}{cccccc} \hline \text{Salt} & \Delta ...
• 2,685
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In the wet medium of an ocean, how does a hard shell form?

Carbon dioxide from the atmosphere (or from decaying matter in the ocean) reacts with water to form carbonic acid: $$\ce{ CO2 + H2O -> H_2CO_3 }$$ and this reacts with calcium ions to form ...
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What is the simplest way to create a precipitation reaction at home?

Here's one easy way : Make a solution of salt ($\ce{NaCl}$) in water, and another solution of Silver Nitrate ($\ce{AgNO_3}$), which you can buy easily) in water. Upon mixing the two, $\ce{AgCl}$ (...
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How do Precipitation Reactions behave in the Absence of Gravity?

In gravityless environment, all directions are equivalent save the very vicinity of the surface(*), where just few water molecules are toward the surface. Therefore, in the bulk volume, the ...
• 29.7k
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Difference between precipitation and crystallisation

The two words are often used interchangeably (perhaps incorrectly), though there is a slight nuance. IUPAC defines the following: Crystallisation: The formation of a crystalline solid from a solution,...
• 16.8k

Why exactly does precipitation occur?

Although you ask specifically about forming precipitates your question is also about the solubility of one substance in another. The simplest answer as to why precipitates form is because the free ...
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Mathematical explanation of blank titration in Mohr method for argentometry

$\ce{AgCl}$ ppts before $\ce{Ag2CrO4}$. But in order to visually detect the $\ce{Ag2CrO4}$ you must add a slight excess of $\ce{Ag^+}$. Hence you use a "blank" with no $\ce{Cl^-}$ to account for the ...
• 21.6k
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Why is only the carbonate anion used to precipitate Barium?

Actually, the textbook should remove this question. You should discuss this with your teacher. It will be a service to future students. The heavier elements of group II elements form insoluble ...
• 33.6k
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Do all double displacement reactions lead to precipitates?

No, recall the definition of a precipitate "insoluble ionic compound". Take this reaction into consideration $$\ce{ NaOH~(s) + HCl~(l) <=> H2O~(l) + NaCl~(aq)}$$ none of the products are ...

Obtain precipitated iron?

Is it possible to obtain pure, precipitated iron with no oxidation by some chemical process? Very pure iron can be obtained by pyrolysis of iron pentacarbonyl. Iron metal obtained in this manner is ...
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Constructing an equation for the precipitation of a salt

Precipitation is usually a single or double displacement reaction, and refers to the formation of an insoluble, solid salt from soluble ions. For instance, silver bromide, $\ce{AgBr}$, is insoluble in ...
• 10.3k
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Why does precipitate always form so naturally?

The ions combine while in solution, and since the resulting compound is not soluble, it precipitates. This happens so quickly because as the precipitate forms, it takes those individual ions out of ...
• 3,818

Difference between precipitation and crystallisation

Both are physical changes. In neither does the substance crystallising/precipitating truely change, in both it is more or less the same after as before. (Technically, ions in solution are something ...
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What is the chemical composition of Turnbull's blue?

Though your textbook is right, Wikipedia isn't completely wrong as in aqueous solution, $\left(\ce{Fe3[Fe(CN)6]2} \right)$ gets converted and is in equilibrium with $\left(\ce{Fe4[Fe(CN)6]3} \right)$ (...
• 612

How to remove sulfuric acid from sample

Sulfuric acid is an excellent dessicant and is also very non-volatile itself (it boils at 337 °C). In other words it would likely still have been there in yet another month. Your instructor ...
• 16.9k
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Aluminium sulphate solubility as function of the pH

The lack of continuity for the curve indicates that the concentration of $\ce{Al2(SO4)3}$ was below the detection limit of the analytical technique being used to measure the concentration of \$\ce{Al2(...
• 21.6k