Answer:
C. Scientists accepted the model at first but later rejected it.
Explanation:
Scientists accepted the model at first because it explained the hydrogen emission spectrum.
However, with the development of quantum mechanics, scientists had to modify the model (not reject it).
Electrons still had specific energies, but they no longer travelled in fixed orbits.
Instead, electrons had a probability of being found in a given region of space.
Answer:
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Answer:
0.39760273
Explanation:
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Answer:
23.46 mmHg is the vapor pressure for the solution
Explanation:
To solve this problem we need to apply a colligative property, which is the lowering vapor pressure.
The formula for this is: P°- P' = P° . Xm
where P' is vapor pressure for solution and P°, vapor pressure for pure solvent.
Let's determine the Xm (mole fraction for solute)
We calculate the moles of the solute and the solvent and we sum each other:
Moles of solute: 60 g /342 g/mol = 0.175 moles of sucrose
Moles of solvent: 250 g / 18 g/mol = 13.8 moles of water
Total moles: 13.8 moles + 0.175 moles = 13.975 moles
Xm for solute: 0.175 moles / 13.975 moles = 0.0125
Let's replace data in the formula: 23.76 mmHg - P' = 23.76 mmHg . 0.0125
P' = - (23.76 mmHg . 0.0125 - 23.76 mmHg) → 23.46 mmHg
