Answer:
12.99
Explanation:
<em>A chemist dissolves 716. mg of pure potassium hydroxide in enough water to make up 130. mL of solution. Calculate the pH of the solution. (The temperature of the solution is 25 °C.) Be sure your answer has the correct number of significant digits.</em>
Step 1: Given data
- Mass of KOH: 716. mg (0.716 g)
- Volume of the solution: 130. mL (0.130 L)
Step 2: Calculate the moles corresponding to 0.716 g of KOH
The molar mass of KOH is 56.11 g/mol.
0.716 g × 1 mol/56.11 g = 0.0128 mol
Step 3: Calculate the molar concentration of KOH
[KOH] = 0.0128 mol/0.130 L = 0.0985 M
Step 4: Write the ionization reaction of KOH
KOH(aq) ⇒ K⁺(aq) + OH⁻(aq)
The molar ratio of KOH to OH⁻is 1:1. Then, [OH⁻] = 0.0985 M
Step 5: Calculate the pOH
We will use the following expression.
pOH = -log [OH⁻] = -log 0.0985 = 1.01
Step 6: Calculate the pH
We will use the following expression.
pH + pOH = 14
pH = 14 - pOH = 14 -1.01 = 12.99
4 moles of sugar.
Explanation:
A mole is defined as the amount of a substance contained in Avogadro's number of particles 6.02 x 10²³.
1 mole of substance = 6.02 x 10²³. molecules
Given that;
the sample of sugar contains 1.505 x 10²³.molecules
The number of moles in this amount of sugar is 4 moles
Learn more:
Number of moles brainly.com/question/13064292
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Yes a red blood cell placed in a sline solution shrinks because of the process of osmosis.
Glycerol attractive forces are great than water. The harder to break, the more energy is needed.
Answer:
A
Explanation:
Same air has special carakteristik features
