Method for making 7.5M ammonium acetate
To make a 7.5M ammonium acetate solution, the first thing to do is to understand the required raw materials and utensils. For raw materials, ammonium acetate ($NH_ {4} C_ {2} H_ {3} O_ {2} $) is also; utensils need a balance, a volumetric bottle, a glass rod, a beaker, etc.

First weigh the appropriate amount of ammonium acetate accurately with a balance. According to the formula $n = C\ times V $ ($n $is the amount of substance, $C $is the amount of substance concentration, $V $is the solution volume), if you want to make $V $liters of 7.5M ammonium acetate solution, the amount of ammonium acetate required is $n = 7.5V $mol. According to the molar mass of ammonium acetate $M $ (about 77.083 g/mol), calculate the required mass of ammonium acetate $m = n\ times M = 7.5V\ times 77.083 $g.

Place the weighed ammonium acetate in a clean beaker, add an appropriate amount of distilled water, and slowly stir with a glass rod to promote its dissolution. During the dissolution process, there may be a little thermal effect, which is normal and there is no need to panic.

After the ammonium acetate is completely dissolved, transfer the solution to the corresponding volume of volumetric flask. When transferring, be sure to keep the glass rod close to the inner wall of the volumetric flask, and the beaker nozzle is also close to the glass rod, so that the solution flows slowly into the volumetric flask along the glass rod to prevent the solution from spilling out.

Wash the beaker and glass rod 2-3 times with a small amount of distilled water, and the washing liquid is also injected into the volumetric bottle to ensure that there is no leakage of solute.

Then add distilled water to the volumetric bottle to be close to the scale line 1-2 cm, and use the glue head dropper to add water dropwise until the concave liquid surface of the solution is tangent to the scale line.

Finally, cover the volumetric bottle with a stopper, turn it upside down and shake it well repeatedly to mix the solution evenly. In this way, the 7.5M ammonium acetate solution is successful.