Answer:
The heat gain by the system,
q
=
−
250
kJ
.
The work done on the system ,
w
=
−
500
kJ
.
The First Law of Thermodynamics state that
Δ
U
=
q
+
w
=
−
750
kJ
Explanation:
The third answer because there are two of each atom
Ok heres what i know, one of the reasons why visible light will pass through glass but not through other materials is because the molecules in glass require more energy than average to push electrons from one level to another. Photons in visible light simply do not have enough energy. Only photons of light with shorter wavelengths, such as those that make up ultraviolet light, have the ability to change the electrons in glass. This is why ultraviolet light is unable to pass through glass. Lol im in 6th grade this is all i know ! :)
Answer:
3
Explanation:
The mass has 4 sig digits.
The volume has 3 sig digits
The density is = 11.50/9.03 = 1.2735
To 3 sig digits (determined by 9.03) the answer would be 1.27 gram/mL
The claim is that NaCl mixture is a homogeneous mixture.
Homogeneous mixture means that the components of the mixtures cannot be determined or separated by the naked eye. However, these components can be separated using physical means, such as boiling, evaporation and condensation which will be used in this experiment.
First, we need to prepare one molar solution of NaCl. To do so, we will dilute a mass of 58.44 grams (molar mass of NaCl) in 1 liter of water.
By this, we will have NaCl solution.
We can notice that once the NaCl is diluted in water, all what you can see is a clear solution. You cannot see the separate particles of NaCl in water.
..............> observation I
Now, we will heat this solution until it boils and water starts evaporating. We will place a cold surface above the steam coming out from the boiling solution.
What we will observe is that when all the water evaporates, we can see white precipitate of NaCl in the bottom of the container. Examining the cold surface placed above the steam, we can see that the water has condensed on this surface.
.........>observation II
Based on this, we managed to use boiling, evaporation and condensation (physical methods) to restore the components of the solution separately.
.............>conclusion
Based on observation I, observation II and the conclusion. we were able to prove that NaCl solution is a homogeneous mixture.
