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Ammonia Dissolved In Water pH
Ammonia dissolves in water pH related analysis
Ammonia is unique and depends on the change of state and pH in water. Ammonia ($NH_3 $) enters water, and a chemical reaction occurs. Ammonia has solitary pairs of electrons, and water contains protons ($H ^ + $). When the two touch, ammonia absorbs protons into ammonium ions ($NH_4 ^ + $), and water contains residual hydroxide ions ($OH ^ - $). The reaction formula is: $NH_3 + H_2O\ rightleftharpoons NH_4 ^ ++ OH ^ - $.
This reaction is not unidirectional and reaches dynamic equilibrium. Ammonia in water only partially interacts with water, so ammonia is a weak base. When the amount of ammonia is different, its equilibrium shifts to different, and the concentration of $OH ^ - $in the solution is also different. According to the definition of pH, $pH = -lg [H ^ +] $, and because the ionic product constant of water is $K_w = [H ^ +] [OH ^ -] $ ($K_w = 1.0\ times10 ^ {-14} $at room temperature), the concentration of $OH ^ - $can be pushed to $H ^ + $concentration, and then the pH is known.
If the ammonia solubility increases, the equilibrium shifts to the right, the concentration of $OH ^ - $rises, the concentration of $H ^ + $drops, and the pH value rises; conversely, the ammonia solubility decreases, the equilibrium shifts to the left, the concentration of $OH ^ - $drops, the concentration of $H ^ + $rises, and the pH value drops. And the temperature also disturbs this equilibrium. If the temperature rises, the equilibrium shifts to the right, the concentration of $OH ^ - $rises slightly, and the pH increases slightly; if it cools down, the opposite is true.
It is necessary that the pH of ammonia soluble in water is controlled by factors such as the amount of ammonia soluble in water and temperature. Research on this is of great significance in the chemical industry, environmental science and other fields.
Ammonia is unique and depends on the change of state and pH in water. Ammonia ($NH_3 $) enters water, and a chemical reaction occurs. Ammonia has solitary pairs of electrons, and water contains protons ($H ^ + $). When the two touch, ammonia absorbs protons into ammonium ions ($NH_4 ^ + $), and water contains residual hydroxide ions ($OH ^ - $). The reaction formula is: $NH_3 + H_2O\ rightleftharpoons NH_4 ^ ++ OH ^ - $.
This reaction is not unidirectional and reaches dynamic equilibrium. Ammonia in water only partially interacts with water, so ammonia is a weak base. When the amount of ammonia is different, its equilibrium shifts to different, and the concentration of $OH ^ - $in the solution is also different. According to the definition of pH, $pH = -lg [H ^ +] $, and because the ionic product constant of water is $K_w = [H ^ +] [OH ^ -] $ ($K_w = 1.0\ times10 ^ {-14} $at room temperature), the concentration of $OH ^ - $can be pushed to $H ^ + $concentration, and then the pH is known.
If the ammonia solubility increases, the equilibrium shifts to the right, the concentration of $OH ^ - $rises, the concentration of $H ^ + $drops, and the pH value rises; conversely, the ammonia solubility decreases, the equilibrium shifts to the left, the concentration of $OH ^ - $drops, the concentration of $H ^ + $rises, and the pH value drops. And the temperature also disturbs this equilibrium. If the temperature rises, the equilibrium shifts to the right, the concentration of $OH ^ - $rises slightly, and the pH increases slightly; if it cools down, the opposite is true.
It is necessary that the pH of ammonia soluble in water is controlled by factors such as the amount of ammonia soluble in water and temperature. Research on this is of great significance in the chemical industry, environmental science and other fields.
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