I have to take a certification for the work that I have been doing for 15 years.
I feel your pain.
For some reason they have a percent solution dilution for chemicals that are ordered now instead of made.
:roll:
% desired:100=g or mL needed:volume desired
Using a colon is one way to write a ratio. Writing a fraction is another way to write the same ratio.
In other words, the expression % desired : 100 denotes the following ratio.
\(\displaystyle \frac{\text{\% desired}}{100}\)
The expression g or ml needed : volume desired denotes the following ratio.
\(\displaystyle \frac{\text{g or ml needed}}{\text{volume desired}}\)
When two ratios have the same value, we call it a proportion.
\(\displaystyle \frac{\text{\% desired}}{100} = \frac{\text{\text{g or ml needed}}}{\text{volume desired}}\)
If you know any two out of the three quantities, the proportion above can be used to find the third quantity.
this is the actual question 500mL of a 3% alcian blue in a 1% acidic acid. Figure the amount of solute needed for the question.
We know two of the three numbers: 3 and 500.
Using the numbers from the given task, we write the proportion.
\(\displaystyle \frac{3}{100} = \frac{\text{g needed}}{500}\)
To solve this equation (i.e., find the third number), we multiply both fractions by 500 because that will eliminate the number 500 from the fraction on the righthand side.
\(\displaystyle \frac{(500)(3)}{100} = \text{g needed}\)
Next, 100 goes into 500 five times; so the 100 cancels, and the 500 becomes 5
\(\displaystyle (5)(3) = \text{g needed}\)
We see that 15g of alcian blue are needed to be disolved into 500mL of the 1% acid solution.
(Oh, by the way, numbers inside parentheses next to one another denotes multiplication. That is, (5)(3) means five times three.)
I have tried setting it up with the 3% of 500mL is _____ and that is as far as I have gotten.
Yes, this will also work.
Remember that "percent" means "per hundred".
Hence, the % symbol means "per 100", so 3% means "3 per 100" or 3/100.
If you divide 3 by 100 on a calculator, you get 0.03.
In other words, 3/100 is the rational form of 3%, and 0.03 is the decimal form of 3%.
We calculate 3% of 500 by multiplying 500 by either the rational form or the decimal form.
(0.03)(500) = 15
