Answer:
Molecular formula
Explanation:
Molecular formula in the first place is required to understand which compound we have. We then should refer to the periodic table and find the molecular weight for each atom. Adding individual molecular weights together would yield the molar mass of a compound.
Then, dividing the total molar mass of a specific atom by the molar mass of a compound and converting into percentage will provide us with the percentage of that specific atom.
E. g., calculate the percent composition of water:
- molecular formula is
; - calculate its molar mass: [tex]M = 2M_H + M_O = 2\cdot 1.00784 g/mol + 16.00 g/mol = 18.016 g/mol;
- find the percentage of hydrogen: [tex]\omega_H = \frac{2\cdot 1.00784 g/mol}{18.016 g/mol}\cdot 100 \% = 11.19 %;
- find the percentage of oxygen: [tex]\omega_O = \frac{16.00 g/mol}{18.016 g/mol}\cdot 100 \% = 88.81 %.
Answer:
101,37°C
Explanation:
Boiling point elevation is one of the colligative properties of matter. The formula is:
ΔT = kb×m <em>(1)</em>
Where:
ΔT is change in boiling point: (X-100°C) -X is the boiling point of the solution-
kb is ebulloscopic constant (0,52°C/m)
And m is molality of solution (mol of ethylene glycol / kg of solution). Moles of ethylene glycol (MW: 62,07g/mol):
203g × (1mol /62,07g) = <em>3,27moles of ethlyene glycol</em>
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Molality is: 3,27moles of ethlyene glycol / (1,035kg + 0,203kg) = 2,64m
Replacing these values in (1):
X - 100°C = 0,52°C/m×2,64m
X - 100°C = 1,37°C
<em>X = 101,37°C</em>
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I hope it helps!
Factors that determine ionization energy:
- Electronic Repulsion - If the electronic density decreases, the ionization energy with increase and vice versa. If an electron gets released, it decreases the electronic repulsion. This makes releasing another electron harder than the first on unless the electron that is being released comes from another energetic level.
- # Of Energy Levels - The more energy cores that get filled up, the more ionization levels decrease. When we see the energy levels go from top to bottom, the ionization also go from most to least. This is why ionization occurs on the highest level.
- Nuclear Charge - The higher the atomic number, the higher charge in the nuclei. This also makes the ionization energy higher as it increases from left to right of in other words, if the nuclear charge gets higer, the energy gets higher as well.
Factors that determine atomic volume:
- How many protons are in the nucleus (nuclear charge)
- How many energy levels carry electrons (electrons in outer energy level)
Best of Luck!
