Answer:
21.9g
Explanation:
This is the answer if you are on edginuity,
Answer:
pH = 2.18
Explanation:
Perchloric acid (HClO₄) is a strong acid. This means that in an aqueous solution it completely dissociates into H⁺ and ClO₄⁻ species.
First we <u>convert 249 mg HClO₄ into moles</u>, using its <em>molecular weight</em>:
- 249 mg HClO₄ ÷ 100.46 mg/mmol = 2.49 mmol HClO₄
<em>Because it is a strong acid</em>, 2.49 mmol HClO₄ = 2.49 mmol H⁺
We <u>calculate the molar concentration of H⁺</u>:
- 2.49 mmol H⁺ / 380 mL = 6.52x10⁻³ M
Finally we <u>calculate the pH of the solution</u>:
- pH = -log[H⁺] = -log(6.52x10⁻³)
Answer:
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Analytical Chemistry 2.1 (Harvey)
2: Basic Tools of Analytical Chemistry
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2.5: Preparing Solutions
Last updatedAug 10, 2020
2.4: Basic Equipment
2.6: Spreadsheets and Computational Software
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Contributed by David Harvey
Professor (Chemistry and Biochemistry) at DePauw University
Preparing a solution of known concentration is perhaps the most common activity in any analytical lab. The method for measuring out the solute and the solvent depend on the desired concentration and how exact the solution’s concentration needs to be known. Pipets and volumetric flasks are used when we need to know a solution’s exact concentration; graduated cylinders, beakers, and/or reagent bottles suffice when a concentrations need only be approximate. Two methods for preparing solutions are described in this section.
Given :
Mass of 
is 571.6 g per liter .
Density of solution , 
.
To Find :
a. Mass percentage
b. Mole fraction
c. Molality
d. molarity of H2SO4 in this solution.
Solution :
Molar mass of , m = 1329 g/mol .
a ) Mass of contain in 1 liter is 1329 g .
b ) Moles of = 
.
Moles of 
= 
.
Mole fraction 
.
c ) Molarity of 
.
Hence , this is the required solution .
