Question

The gram formula weight of phosphoric acid is $98.00{\text{ }}g/mol$, and the density of $85.0\%$ phosphoric acid is $1.685{\text{ }}g/mL$. Could you describe how to prepare $500{\text{ }}mL$ of a $1.0{\text{ }}M$ solution of phosphoric acid from $85.0\%$ phosphoric acid ?

Answer 1

Phosphoric acid is also acknowledged as orthophosphoric acid is a weak acid. It is white crystal like solid. It is colourless, viscous, and less solid. It is non unstable and non toxic in nature. Magnesium hydroxide is an inorganic compound which is a smaller amount soluble in water. It is shaped from mineral brucite.

Complete step by step answer: You must type the following conversions:$Volume{\text{ }}of{\text{ }}dilute{\text{ }}acid{\text{ }} \to {\text{ }}moles{\text{ }}of{\text{ }}{H_3}P{O_4} \to {\text{ }}mass{\text{ }}of{\text{ }}{H_3}P{O_4} \to {\text{ }}mass{\text{ }}of{\text{ }}conc.{\text{ }}Acid{\text{ }} \to {\text{ }}volume{\text{ }}of{\text{ }}conc.{\text{ }}Acid$Now we go:$0.500L{\text{ }}dil.{\text{ }}Acid{\text{ }}*\left( {1.0mol\;{H_3}P{O_4}/{\text{ }}1L{\text{ }}dil.{\text{ }}Acid} \right){\text{ }}*{\text{ }}\left( {98.00{\text{ }}g{\text{ }}{H_3}P{O_4}/{\text{ }}1mol{\text{ }}{H_3}P{O_4}} \right){\text{ }}*\left( {100g{\text{ }}conc.{\text{ }}Acid{\text{ }}/{\text{ }}85g\;{H_3}P{O_4}} \right){\text{ }}*{\text{ }}\left( {1mL{\text{ }}conc.{\text{ }}Acid{\text{ }}/{\text{ }}1.685g{\text{ }}conc.{\text{ }}Acid} \right){\text{ }} = {\text{ }}34{\text{ }}mL{\text{ }}conc.{\text{ }}acid$ So, you would add $34{\text{ }}mL$ of $85.0\%$ phosphoric acid to sufficient distilled water to make a whole of $500{\text{ }}mL$.
The answer can have individual two significant figures, because that is all you presented for the molarity of the dilute acid and the percent concentration of the concentrated acid. If you need more accuracy, you will have to recalculate.

Additional information - Phosphoric acid seems to be a clear colorless liquid or transparent crystalline solid. The unalloyed solid melts at $42.35^\circ C$ and has a density of $1.834{\text{ }}g{\text{ }}/{\text{ }}c{m^3}$. Liquid is regularly an $85.0\%$ aqueous solution. Sent as together a solid and liquid. Acid to metals and tissue. Used in creating fertilizers and detergents and in food processing.

Note:
Phosphoric acid can form dimmers, trimmers at high temperature, As it has three expendable hydrogen so it forms three different kinds of salts. Phosphoric acid can be made by a damp process. Magnesium hydroxide is a food chemical, used as fire retardant, in gold mining, silos. It is also recycled to quiet chronic constipation as laxative.