Answer:
Mole fraction of solute is 0.0462
Explanation:
To solve this we use the colligative property of lowering vapor pressure.
First of all, we search for vapor pressure of pure water at 25°C = 23.8 Torr
Now, we convert the Torr to mmHg. Ratio is 1:1, so 23.8 Torr is 23.8 mmHg.
Formula for lowering vapor pressure is:
ΔP = P° . Xm
Where ΔP = P' (Vapor pressure of solution) - P° (Vapor pressure of pure solvent)
Xm = mole fraction
24.9 mmHg - 23.8 mmHg = 23mmHg . Xm
Xm = (24.9 mmHg - 23.8 mmHg) / 23mmHg
Xm = 0.0462
Bohr's atomic model proposed that electrons move in specific orbits around the nucleus of an atom.
Lithium Bromine (LiBr) is formed from them....
Answer:
C.) 35
Explanation:
The mass is made up of the total protons and neutrons in an atom. Protons and neutrons both have a mass of 1 amu. Electrons are not included in this measurement because they have an insignificant mass (practically 0).
(17 protons x 1 amu) + (18 neutrons x 1 amu) = 35 amu
Therefore, if an atom contains 17 protons and 18 neutrons, the mass should be 35 amu.
Answer:
The average kinetic energy of a gas depends only on its temperature.
Explanation:
The average kinetic energy of particles in a gas can be found using the equation
,
where
is the Stefan-Boltzmann constant, and
is the absolute temperature of this gas (the one in degree Kelvins.)
As seen in this equation, the average kinetic energy of particles in a gas depends only on the temperature of the gas. Also, since the question is asking for the average not the total kinetic energy, the number of particles in this gas doesn't matter, either.
