Explanation:
The work is to calculate the molar mass of the solute (adrenaline) from the elevation of the boling point and compare with the mass of the structural formula. If they both are reasonably equal then you conclude that the results are in agreement, else they are not in agreement.
Since, you did not include the structural formula, I can explain the whole procedure to calculate the molar mass from the boiling point elevation, and then you can compare with the mass of the structural formula that only you know.
Determination of the molar mass from the boiling point elevation.
1) With the elevation of the boiling point, which is a colligative property, you can find the molality of the solution, using the formula:
ΔTb = i * Kb * m
Where:
> ΔTb is the increase of the boiling point of ths solvent, i.e. CCl4.
> i van't Hoff constant = 1 (because the solute is non ionic)
> m is the molality of the solution
2) Clearing m you get:
m = ΔTb / Kb
Kb is a datum that you must find in a table of internet (since the statement does not include it).
I found Kb = 5.02 °C/m
Then, m = 0.49°C / (5.02°C/m) = 0.09760956 m
3) With m and the mass of solvent you find the number of moles of solute using the formula:
m = number of moles of solute / kg of solvent
You have the mass of the solvent = 36.0 g = 0.0360 kg, so you can solve for the number of moles of solute:
=> number of moles of solute = m * kg of solvent = 0.09760956 m * 0.036kg = 0.0035139 moles
4) With the nuimber of moles and the mass you find the molar mass:
molar mass = mass in grams / number of moles = 0.64 g / 0.0035139 moles = 182 g/mol <------------- this is the important result
5) Now that you have the molar mass you can compare with the mass of the molecular formula. If they are reasonably equal then you conclude that the <span>molar mass of adrenaline calculated from the boiling point elevation is in agreement with the structural formula</span>
Answer:
Eon-an indefinite and very long period of time, often a period exaggerated for humorous or rhetorical effect.
Era
Paleozoic-its end was marked by mass extinctions
mesozoic-between cenozoic and paleozoic
cenozoic- most recent era
period-a length of time
epoch-age
mass extinction- a huge die off of animals
landbridge- a strip of land connecting two large land masses
geographic isolation-island
Explanation:
They should report the density as 1.11 g/L
.
Density = mass/volume = 2.260g/2.04 mL
My calculator says the density <em>1.107 843 137 g/mL</em>
However, the answer can have <em>no more</em> significant figures than are in the number with the <em>fewest </em>significant figures.
The volume measurement has only three significant figures, so we must round off the density to three significant figures.
We drop all the digits after the zero.
The digit to be dropped is 7, so we <em>round up </em>the last significant figure of the answer.
1.10<u>7 843 137</u> → 1.11
<h3>
Answer:</h3>
Atoms of elements on the reactants side
- 2 Carbon atoms
- 6 Hydrogen atoms
- 7 Oxygen atoms
<h3>
Explanation:</h3>
- The equation; C₂H₅OH+ 3O₂ →2CO₂+ 3H₂O is balanced.
- A balanced chemical equation has an equal number of atoms of each element on either side of the equation.
- For example, in the equation given, the number of atoms of each element is equal on both sides of the equation.
- There are 2 carbon atoms, 6 hydrogen atoms, and 7 hydrogen atoms on either side of the equation.
- According to the law of conservation of mass, the mass of the reactants should be equal to the mass of reactants.
- Therefore, chemical equations are balanced for them to obey the law of conservation of mass.
