Answer:
- <u><em>He must use 50g of the 12% solution and 30 g of the 20% solution.</em></u>
<u><em></em></u>
Explanation:
Call x the amount of <em>12% boric acid </em>solution to be used.
- The content of acid of that is: 0.12x
Since he wants to make <em>80 grams</em> of solution, the amount of <em>20% boric acid</em> solution to be used is 80 - x.
- The content of acid of that is{ 0.20(80 - x).
The final solution is <em>15% </em>concentrated.
- The content of boric acid of that is 0.15 × 80 g.
Now you have can write your equation:

Solve:

That is 50 grams of the 12% solution of boric acid.
Calculate the amount of the 20% solution of boric acid:

That is 30 grams.
Then, he must use 50g of the 12% solution and 30 g of the 20% solution.
Answer:
178.98 sq. feet
Explanation:
The path and the garden has been shown in the figure below. The green area is the garden and the area in brown is the path.
It has been given that,
Radius of garden = 8 feet
So, the area of garden = 3.14 × 8 × 8 = 200.96 sq. feet
The total radius of the land including garden and path = 8 + 3 = 11 feet
So, the total are of land including garden and path = 3.14 × 11 × 11 = 379.94 sq. feet
So, the area of path = Total area of the land - area of garden
Area of path = 379.94 - 200.96 = 178.98 sq. feet
Answer:
0.500 mole of Xe (g) occupies 11.2 L at STP.
General Formulas and Concepts:
<u>Gas Laws</u>
- STP (Standard Conditions for Temperature and Pressure) = 22.4 L per mole at 1 atm, 273 K
<u>Stoichiometry</u>
- Mole ratio
- Dimensional Analysis
Explanation:
<u>Step 1: Define</u>
<em>Identify.</em>
0.500 mole Xe (g)
<u>Step 2: Convert</u>
- [DA] Set up:

- [DA] Evaluate:

Topic: AP Chemistry
Unit: Stoichiometry