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If some $\ce{AgCl(s)}$ is introduced into a bromide solution, it reacts with $\ce{Br-}$ ions according to : $$\ce{AgCl(s) + Br- -> AgBr(s) + Cl-}$$ so that $\ce{AgCl}$ is quickly transformed into $\ce{AgBr}$ which is nearly insoluble in, for example, $\ce{NH3}$ solution. So if some $\ce{AgNO3}$ is added to a solution containing both $\ce{Br-}$ and $\ce{...


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All depends on the particular scenario. Let assume the concentrations of both halogenides and silver nitrate are low enough, so only the solubility product of silver bromide is reached. Then silver bromide is precipitated selectively ( if we neglect coprecipitation effects ). Similar effect is achieved, if nitrate is being added so slowly the reprecipitation ...


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Yes, technically they can precipitate cations from lower groups. However, while doing the analysis, due consideration is given to the concentration of the added reagent so that unwanted cations do not precipitate. For example, cations of group 2 and group 4 are both precipitated as sulfides. On the other hand, since group 2 cations require lower ...


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There is an dark side of HPLC with biological samples...with time, silica bonded column becomes a protein or a "bio-gunk" column, instead of a C18 column because of very strong adsorption of biomolecules on the surface. I gather your main problem is the pressure increase with these samples and the manufacturer's recommendation to wash with 2-...


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The statement is true if the mass concentration (e.g., $\pu{g//L}$) of polymers in solution is constant, but false if the number concentration (e.g.,$\pu{mol//L}$) of polymers in solution is constant. Here are some examples corresponding to the above. Let's start with the second case: Increase molar mass while keeping the number concentration of polymers ...


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