<span>1. Which variable is the independent variable and which is the dependent variable? Density vs. ethylene glycol
The independent variable would be ethylene glycol and dependent variable would be density.
A. A 25-mL volumetric flask with its stopper has a mass of 32.6341 g. The same flask filled to the line with ethylene glycol (C2H6O2, automotive antifreeze) solution has a mass of 58.0091 g. What is the density of the ethylene glycol solution?
Density = 58.0091 - 32.6341 / .025 = 1015 g/L
B. What is the molarity of the ethylene glycol solution, if the mass of ethylene glycol in the solution is 12.0439 g?
Molarity = 12.0439 ( 1 mol / 62.07 g) / 0.025 = 7.8 M</span>
Answer : The correct option is, (A)
because one of each is produced every time an
transfers from one water molecule to another.
Explanation :
As we know that, when the two water molecule combine to produced hydronium ion and hydroxide ion.
The balanced reaction will be:

Acid : It is a substance that donates hydrogen ion when dissolved in water.
Base : It is a substance that accepts hydrogen ion when dissolved in water.
From this we conclude that, the hydrogen ion are transferred from one water molecule to the another water molecule to form hydronium ion and hydroxide ion. In this reaction, one water molecule will act as a base and another water molecule will act as an acid.
Hence, the correct option is, (A)
The words aa q.s. is an abbreviation which is used in
pharmacy. This is usually written by prescribers and then translated by
pharmacists. The aa is derived from Latin which means “of each” while q.s. is
also derived from Latin which means “a sufficient quantity”. This simply means
that there is equal amount of Hytone 1% cream and Lotrimin 1% cream in the
total cream formulation.
Since we are to make a total of 60 g of cream, therefore
50% of it would be Lotrimin cream.
Amount of Lotrimin cream needed = 0.5 (60 g)
<span>Amount of Lotrimin cream needed = 30 grams</span>