239.0 g/mol
Add the mass of each individual atom
Answer:
4.87g
Explanation:
Step 1:
Data obtained from the question. This includes the following:
Mass of solution = 0.35kg
Molality = 0.238 m
Mass of NaCl =..?
Step 2:
Determination of the number of mole of NaCl in the solution.
Molality of a solution is simply defined as the mole of solute per unit kg of the solvent. It is given as:
Molality = mol of solute /mass of solvent (kg)
With the above formula, we calculate the mole of NaCl present in the solution as follow:
Molality = mol of solute /mass of solvent (kg)
0.238 = mol of NaCl /0.35
Cross multiply
mol of NaCl = 0.238 x 0.35
mol of NaCl = 0.0833 mol
Step 3:
Determination of the mass of NaCl in 0.0833 mol of NaCl.
This is illustrated below:
Number of mole NaCl = 0.0833 mol
Molar Mass of NaCl = 23 + 35.5 = 58.5g/mol
Mass of NaCl =..?
Mass = number of mole x molar Mass
Mass of NaCl = 0.0833 x 58.5
Mass of NaCl = 4.87g
Therefore, 4.87g of NaCl is contained in the solution.
Answer:
13.2 g Na2CO3
Explanation:
Convert 10.0 g NaOH to mol.
10.0 g x 1 mol/39.997 g = 0.250 mol
Use mol ration given by the equation: 2 mol NaOH to 1 mol Na2CO3
0.250 mol NaOH x 1 mol Na2CO3/2 mol NaOH = 0.125 mol Na2CO3
Finally, convert the moles of Na2CO3 to grams.
0.125 mol Na2CO3 x 105.99 g/1 mol = 13.2 g
Hey it's me again haha!
the answer to your question is:
answer: so f=20.1
a=8.2
m=?
f=ma
20.1 = 8.2*m in
20.1/8.2=m
so the answer is around 2.45 something!
also i'm sorry this question had be stumbled!
The pH of a solution which is 0.023 m in weak base and 0 037 m in the conjugate weak acid whose Ka= 7.1 × 10⁻⁶ is 4.93.
pH determines the amount of hydrogen and hydroxide ions in a solution. It is the negative logarithm of hydrogen ion concentration.
Given,
Ka= 7.1 × 10⁻⁶
Weak base = 0.023M
Acid = 0.037M
Using base dissociation constant, Ka we can calculate pKa by:
pKa = -log [Ka]
pKa = -log [7.1 × 10⁻⁶]
pKa = 5.15
A weak base and its conjugate acid are present in equal proportions in buffer solution. Using the Henderson-Hasselbalch equation, we can find out the pH of a buffer solution that constitutes a weak base and its conjugate acid.
Using Henderson-Hasselbalch equation,
pH = pKa + log [Weak base / acid]
pH = 5.15 + log [0.023 / 0.037]
pH = 5.15 + log[0.6]
pH = 5.15 - 0.22
pH = 4.93
Therefore, the pH of the solution is 4.93.
Learn more about pH here, brainly.com/question/22390063
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