Preparation of 0.01m ammonium acetate

1. Required materials
1. ** acetic acid (CH < COOH) **: analytical purity grade, used to provide acetate ion.
2. ** ammonia water (NH < H < O) **: analytical purity grade, used to provide ammonium ion.
3. ** distilled water **: used to dissolve and dilute, to ensure the purity of the solution.
4. ** Instrument **: electronic balance, volumetric flask (select the appropriate specifications according to the required solution volume, such as 100mL, 250mL, etc.), measuring cylinder, glass rod, rubber head dropper, beaker.

2. Operation steps
1. ** Calculation **: According to the quantity concentration formula of the substance\ (c = n/V\) (\ (c\) is the quantity concentration of the substance,\ (n\) is the quantity of the solute substance,\ (V\) is the solution volume), to prepare the volume of\ (V\) (set\ (V = 100mL = 0.1L\)) of\ (0.01m\) ammonium acetate solution, ammonium acetate (\ (CH 🥰 COONH\)) molar mass\ (M = 77.083g/mol\). \ (n = cV = 0.01mol/L × 0.1L = 0.001mol\), then the required mass of ammonium acetate\ (m = nM = 0.001mol × 77.083g/mol Technologies 0.077g\). Since in actual operation, acetic acid is commonly prepared by reacting with ammonia, according to the chemical equation\ (CH < unk > COOH + NH < unk > · H < unk > O = CH < unk > COONH < unk > + H < unk > O\), it can be seen that the ratio of acetic acid to ammonia is\ (1:1\), and the required amount of acetic acid and ammonia is calculated. If you use acetic acid with a mass fraction of\ (36\% - 38\%\) and a density of about\ (1.05g/mL\), let the required volume of acetic acid be\ (V\),\ (n (CH < unk > COOH) = n (CH < unk > COONH) = 0.001mol\),\ (c (CH < unk > COOH) =\ frac {1000 ω} {M} =\ frac {1000 × 1.05 × 0.37} {60.05} mol/L < unk > 6.5mol/L \)（\(ρ\) is the density of acetic acid,\ (ω\) is the mass fraction of acetic acid,\ (M\) is the molar mass of acetic acid), from\ (c < unk > V= n\), we can get\ (V < unk =\ frac {n} {c} =\ frac {0.001mol} {6.5mol/L} Technologies 0.15mL\); if you use ammonia with a mass fraction of\ (25\% - 28\%\) and a density of about\ (0.91g/mL\), set the required ammonia volume to\ (V ³\),\ (c (NH < unk > · H < unk > O) =\ frac {1000μω} {M} =\ frac {1000 × 0.91 × 0.26} {17.03} mol/L < unk > 14mol/L \)（\(ρ\) is the density of ammonia,\ (ω\) is the mass fraction of ammonia,\ (M\) is the molar mass of ammonia), from\ (c < unk > V < unk > = n\), you can get\ (V < unk > =\ Frac {n} {c ³} =\ frac {0.001mol} {14mol/L} Technologies 0.07mL\).
2. ** Measurement **: Accurately measure the calculated volume of acetic acid and ammonia with a measuring cylinder of the appropriate range. When measuring acetic acid, tilt the measuring cylinder. The mouth of the reagent bottle is next to the mouth of the measuring cylinder. Slowly pour acetic acid until it is close to the desired scale. Instead, use a rubber head dropper to add it dropwise to the scale line; the operation of measuring ammonia is similar.
3. ** Reaction **: Slowly pour the measured acetic acid into a beaker containing an appropriate amount of distilled water, and gently stir with a glass rod. Then slowly pour the measured ammonia into the beaker, and stir while pouring. At this time, a neutralization reaction occurs to generate ammonium acetate, and heat will be released. Stirring can disperse the heat evenly.
4. ** Transfer **: After the solution is cooled to room temperature, drain with a glass rod, and transfer the solution to a pre-washed and dried volumetric flask. Make sure that all the solution is transferred, wash the beaker and glass rod\ (2 - 3\) times with a small amount of distilled water, and the washing liquid is also transferred to the volumetric bottle to ensure that all the solutes are transferred.
5. ** Bandwidth evaluation **: Add distilled water to the volumetric bottle to the point where the liquid level is away from the scale line\ (1 - 2cm\), use the rubber head dropper to add water dropwise, and look at the scale line with your eyes until the lowest point of the concave liquid level of the solution is tangent to the scale line.
6. ** Shake well **: Cover the volumetric bottle cork, put your index finger against the cork, and hold the bottom of the bottle with your other hand. Repeatedly turn it upside down and shake the solution well to make the solution concentration uniform.

III. Precautions
1. Both acetic acid and ammonia have volatile and irritating odors. The operation should be carried out in a well-ventilated environment, such as a fume hood, to avoid inhaling harmful gases.
2. When measuring acetic acid and ammonia, accurate readings should be made. When reading, the line of sight should be kept at the lowest point of the liquid concave liquid level in the measuring cylinder.
3. When transferring the solution, be sure to ensure that all the solutions are transferred to the volumetric flask, and the volumetric flask specifications should match the required solution volume to ensure accurate solution concentration.
4. During bandwidth evaluation, the rubber head dropper should not extend into the volumetric flask to prevent contamination of the solution.