Answer: C
Explanation:
Hot air is a lot less dense for a few reasons. Hot air essentially means the particles have more kinetic energy, and move around a lot more. Cold air is dense because the particles move a lot less, have less energy, and are closer together.
Answer:
3M
Explanation:
moles ÷ liters = molarity
4.8 ÷ 1.6 = 3M
<span>In the Bohr model electrons in atoms can occupy allowed orbits where they do not emit energy. Exchange of energy with the surrounding environment occurs only when an electron "jumps" from an orbit to another. Hope this answers the question. Have a nice day.</span>
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
First, you mix the salt and sand with water, so the salt dissolves. Next, you filter the sand out, so you have the slat water and sand separated. Then, you evaporate the water, leaving the salt behind.
