Answer:
1. ΔE = 0 J
2. ΔH = 0 J
3. q = 3.2 × 10³ J
4. w = -3.2 × 10³ J
Explanation:
The change in the internal energy (ΔE) and the change in the enthalpy (ΔH) are functions of the temperature. If the temperature is constant, ΔE = 0 and ΔH = 0.
The gas initially occupies a volume V₁ = 20.0 L at P₁ = 3.2 atm. When the pressure changes to P₂ = 1.6 atm, we can find the volume V₂ using Boyle's law.
P₁ × V₁ = P₂ × V₂
3.2 atm × 20.0 L = 1.6 atm × V₂
V₂ = 40 L
The work (w) can be calculated using the following expression.
w = - P . ΔV
where,
P is the external pressure for which the process happened
ΔV is the change in the volume
w = -1.6 atm × (40L - 20.0L) = -32 atm.L × (101.325 J/1atm.L) = -3.2 × 10³ J
The change in the internal energy is:
ΔE = q + w
0 = q + w
q = - w = 3.2 × 10³ J
Answer:
C: The shape of the pebbles is a result of weathering and deposition
Explanation:
For the several pebbles to have a rounded shape and smooth to the touch, it will undergo weathering and deposition. This is because weathering involves breaking down of rocks and creating new sediments. This weathering could be either chemical weathering or physical weathering where Chemical weathering is the decomposition of rocks which are caused by chemical reactions and which result in formation of new compound while physical weathering is the breakdown of rocks into smaller pieces. On the other hand, deposition occurs when the agents of erosion such as wind or water deposit sediments from one spot to another which in turn changes the shape of the land.
Thus, the shape of the pebbles are as a result weathering of the parent rocks and from deposition.
Answer:
11482 ppt of Li
Explanation:
The lithium is extracted by precipitation with B(C₆H₄)₄. That means moles of Lithium = Moles B(C₆H₄)₄. Now, 1 mole of B(C₆H₄)₄ produce the liberation of 4 moles of EDTA. The reaction of EDTA with Mg²⁺ is 1:1. Thus, mass of lithium ion is:
<em>Moles Mg²⁺:</em>
0.02964L * (0.05581mol / L) = 0.00165 moles Mg²⁺ = moles EDTA
<em>Moles B(C₆H₄)₄ = Moles Lithium:</em>
0.00165 moles EDTA * (1mol B(C₆H₄)₄ / 4mol EDTA) = 4.1355x10⁻⁴ mol B(C₆H₄)₄ = Moles Lithium
That means mass of lithium is (Molar mass Li=6.941g/mol):
4.1355x10⁻⁴ moles Lithium * (6.941g/mol) = 0.00287g. In μg:
0.00287g * (1000000μg / g) = 2870μg of Li
As ppt is μg of solute / Liter of solution, ppt of the solution is:
2870μg of Li / 0.250L =
<h3>11482 ppt of Li</h3>
Explanation:
The given data is as follows.
Energy of radiation absorbed by the electron in hydrogen atom = 
As energy is absorbed as a photon. Hence, frequency will be calculated will be as follows.
E = 
= 
= 
or, = 
It is known that, 
= 
And, according to De-Broglie equation 
as, p = 
So, 
= 
Now, on squaring both the sides we get the following.
= 
= 
where, m = mass of electron
So,
= 
= 
J
Since, K.E = 
= 
= 
Thus, we can conclude that kinetic energy acquired by the electron in hydrogen atom is 
.
Answer:
6,216.684 kilograms of sodium carbonate must be added to neutralize 
of sulfuric acid solution.
Explanation:
Mass of sulfuric acid solution = 
Percentage mass of sulfuric acid = 95.0%
Mass of sulfuric acid = 
Moles of sulfuric acid = 
According to reaction , 1 mole of sulfuric acid is neutralized by 1 mole of sodium carbonate.
Then 58,647.96 moles of sulfuric acisd will be neutralized by :
of sodium carbonate
Mass of 58,647.96 moles of sodium carbonate :
6,216,683.76 g = 6,216,683.76 × 0.001 kg = 6,216.684 kg
6,216.684 kilograms of sodium carbonate must be added to neutralize of sulfuric acid solution.
