Answer:
- m = 1,000/58.5
- b = - 1,000 / 58.5
1) Variables
- molarity: M
- density of the solution: d
- moles of NaCl: n₁
- mass of NaCl: m₁
- molar mass of NaCl: MM₁
- total volume in liters: Vt
- Volume of water in mililiters: V₂
- mass of water: m₂
2) Density of the solution: mass in grams / volume in mililiters
3) Mass of NaCl: m₁
Number of moles = mass in grams / molar mass
⇒ mass in grams = number of moles × molar mass
m₁ = n₁ × MM₁
4) Number of moles of NaCl: n₁
Molarity = number of moles / Volume of solution in liters
M = n₁ / Vt
⇒ n₁ = M × Vt
5) Substitue in the equation of m₁:
m₁ = M × Vt × MM₁
6) Substitute in the equation of density:
d = [M × Vt × MM₁ + m₂] / (1000Vt)
7) Simplify and solve for M
- d = M × Vt × MM₁ / (1000Vt) + m₂/ (1000Vt)
- d = M × MM₁ / (1000) + m₂/ (1000Vt)
Making the simplistic assumption that the dissolved NaCl(s) does not affect the volume of the solvent water means 1000Vt = V₂
- d = M × MM₁ / (1000) + m₂/ V₂
m₂/ V₂ is the density of water: 1.00 g/mL
- d = M × MM₁ / (1000) + 1.00 g/mL
- M × MM₁ / (1000) = d - 1.00 g/mL
- M = [1,000/MM₁] d - 1,000/ MM₁
8) Substituting MM₁ = 58.5 g/mol
- M = [1,000/58.5] d - [1,000/ 58.5]
Comparing with the equation Molarity = m×density + b, you obtain:
- m = 1,000/58.5
- b = - 1,000/58.5
Can you show the question that goes with those answer pls
Answer:
The molar mass of the unknown acid is 386.8 g/mol
Explanation:
Step 1: Data given
Mass of the weak acid = 1.168 grams
volume of NaOH = 28.75 mL = 0.02875 L
Molarity of NaOH = 0.105 M
Since we only know 1 equivalence point, we suppose the acid is monoprotic
Step 2: Calculate moles NaOH
Moles NaOH = molarity NaOH * volume NaOH
Moles NaOH = 0.105 M * 0.02875 L
Moles NaOH = 0.00302 moles
We need 0.00302 moles of weak acid to neutralize the NaOH
Step 3: Calculate molar mass of weak acid
Molar mass = mass / moles
Molar mass = 1.168 grams / 0.00302 moles
Molar mass = 386.8 g/mol
The molar mass of the unknown acid is 386.8 g/mol
Chemical
bonds between atoms in reactants undergo change during a chemical
reaction.
<span>The substance (or substances) initially involved in a </span>chemical reaction<span> <span>are
called reactants or reagents. </span></span>Chemical reactions<span> <span>are
usually characterized by a </span></span>chemical<span> change,
and they yield one or more products, which usually have properties different
from the reactants.</span>
The correct answer between all
the choices given is the last choice or letter D. I am hoping that this answer
has satisfied your query and it will be able to help you in your endeavor, and
if you would like, feel free to ask another question.
Answer:
4.52 mol/kg
Explanation:
Given data:
Mass of lithium fluoride = 22.1 g
Mass of water = 188 g
Molality = ?
Solution:
Molality:
It is the number of moles of solute into kilogram of solvent.
Formula:
Molality = number of moles of solute / kilogram solvent
Mathematical expression:
m = n/kg
Now we will convert the grams of LiF into moles.
Number of moles = mass/ molar mass
Number of moles = 22.1 g/ 26 g/mol
Number of moles = 0.85 mol
Now we will convert the g of water into kg.
Mass of water = 188 g× 1kg/1000 g = 0.188 kg
Now we will put the values in formula.
m = 0.85 mol / 0.188 kg
m = 4.52 mol/kg
