Mass NaCl = 4.348
Mass solution = 21.040 - 4.348 = 16.692
mass/mass % =
4.348/16.692
= 26%
mass/vol % =
21.7%
Molecular mass of NaCl = 58.5
Moles of NaCl = 0.074
Volume of solution = 0.02 L
Molarity = 3.7 mol/Liter
Answer:
The wavelength the student should use is 700 nm.
Explanation:
Attached below you can find the diagram I found for this question elsewhere.
Because the idea is to minimize the interference of the Co⁺²(aq) species, we should <u>choose a wavelength in which its absorbance is minimum</u>.
At 400 nm Co⁺²(aq) shows no absorbance, however neither does Cu⁺²(aq). While at 700 nm Co⁺²(aq) shows no absorbance and Cu⁺²(aq) does.
The answer is: " 56 g CaCl₂ " .
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Explanation:
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2.0 M CaCl₂ = 2.0 mol CaCl₂ / L ;
Since: "M" = "Molarity" (measurement of concentration);
= moles of solute per L {"Liter"} of solution.
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Note the exact conversion: 1000 mL = 1 L .
Given: 250 mL ;
250 mL = ? L ? ;
250 mL * (1 L / 1000 L) = (250/1000) L = 0.25 L .
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(2.0 mol CaCl₂ / L ) * (0.25L) = (2.0) * (0.25) mol = 0.50 mol CaCl₂ ;
We have: 0.50 mol CaCl₂ ; Convert to "g" (grams):
→ 0.50 mol CaCl₂ .
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1 mol CaCl₂ = ? g ?
From the Periodic Table of Elements:
1 mol Ca = 40.08 g
1 mol Cl = <span>35.45 g .
</span>
There are 2 atoms of Cl in " CaCl₂ " ;
→ Note the subscript, "2", in the " Cl₂ " ;
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So, to calculate the molar mass of "CaCl₂" :
40.08 g + 2(35.45 g) =
40.08 g + 70.90 g = 110.98 g ; round to 4 significant figures;
→ round to 111 g/mol .
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So:
→ 0.50 mol CaCl₂ = ? g CaCl₂ ? ;
→ 0.50 mol CaCl₂ * (111 g CaCl₂ / mol CaCl₂) ;
= (0.50) * (111 g) CaCl₂ ;
= 55.5 g CaCl₂ ;
→ round to 2 significant figures;
→ 56 g CaCl₂ .
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The answer is: " 56 g CaCl₂ " .
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<h2>
YeS im Am fRom pLanet k12 And brinG anD imPortant MesSage </h2>
- The answer to your question is, <u><em>There are only so many ways matter can arrange itself within that infinite universe.</em></u>
<h2>
<em>Also if your on the same test as me heres some other sTuff that was on my test </em></h2><h2>
<em> </em></h2>
Question 1 (1 point)
In Brian Greene's "A Physicist Explains Why Parallel Universes May Exist", what reason does Greene give for why he believes parallel universes may exist?
- <em>Answer: There are only so many ways matter can arrange itself within that infinite universe.</em>
<em> </em>
Question 2 (1 point)
Choose the best explanation for why we experience the Mandela Effect.
- <em>Answer: Our brains tend to fill in information that we cannot readily recall and make associations that are not true.</em>
Question 3 (1 point)
From the article "Time Travel Is A Fun Science Fiction Story But Could It Be Real?", Albert Einstein's Theory of Relativity is described as what?
- <em>Answer: The pulling force of gravity causes space to curve and causes time to slow down.</em>
Question 4 (1 point)
From the video " Are Wormholes The Answer To Time Travel?", how are worm holes described?
- <em>Answer: A tunnel in space connecting two regions very distant from each other. A "short cut" through space</em>
Question 5 (1 point)
Many scientists think human cloning is possible, so why haven't we made human clones yet?
- <em>Answer: Human cloning is extremely controversial and many people believe it is unethical</em>
<h2><em>
HOPE THIS HELPS ANYONE IF IT DOES THANK AND RATE FOR A FREE COOKIE :D
</em></h2>
Answer:
They experience the same pressure
Explanation:
To answer this question, we recall Pascal's, Law Pascal's law states that an increase in pressure at a point in a confined cylinder containing a fluid, there is also an equal increase at all other points in that cylinder.
According to Pascal's law the pressure if the pressure expereienced by the larger diameter piston increases, the pressure experienced by the smaller diameter piston also increases by the same amount
However considering that pressure = Force/area F1/A1 =F2/A2
thus where A1 = πD²÷4 and A2 = πD²÷ 16 we have
we have F1×4/πD² = F2×16/πD² or F1 = 4× F2
They experience the same pressure but the larger cylinder delivers four times the force transmitted from he outside to the smaller cylinder
