Answer:
itd be B because the melting point is 29.76 no matter the size
Explanation:
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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>
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<em>Also if your on the same test as me heres some other sTuff that was on my test </em></h2><h2>
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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>
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HOPE THIS HELPS ANYONE IF IT DOES THANK AND RATE FOR A FREE COOKIE :D
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Answer:
ΔH = -470.4kJ
Explanation:
It is possible to sum 2 or more reactions to obtain the ΔH of the reaction you want to study (Hess's law). Using the reactions:
1. CaC2(s) + 2H2O(l) → C2H2(g) + Ca(OH)2(s)ΔH = −414kJ
2. 6C2H2(g) + 3CO2(g) + 4H2O(g) → 5CH2CHCO2H(g)ΔH = 132kJ
6 times the reaction 1.
6CaC2(s) + 12H2O(l) → 6C2H2(g) + 6Ca(OH)2(s)ΔH = −414kJ*6 = -2484kJ
This reaction + 2:
6CaC2(s) + 3CO2(g) + 16H2O(l) → + 6Ca(OH)2(s) + 5CH2CHCO2H(g) ΔH = -2484kJ + 132kJ = -2352kJ
As we want to calculate the net change enthalpy in the formation of just 1 mole of acrylic acid we need to divide this last reaction in 5:
6/5CaC2(s) + 3/5CO2(g) + 16/5H2O(l) → + 6/5Ca(OH)2(s) + CH2CHCO2H(g) ΔH = -2352kJ / 5
<h3>ΔH = -470.4kJ</h3>
First, we must know what happens in the precipitation reaction. This type of reaction is a double replacement reactions. It is consists of two reactant compounds which interchange cations and anions to form two products. One of the products is an insoluble solid called a precipitate. For the precipitation of CaCO₃, there are two consecutive reactions involved:
1. Slaking of quicklime, CaO
CaO + H₂O ⇒ Ca(OH)₂
2. Precipitation
Ca(OH)₂ + CO₂ ⇒ CaCO₃ + H₂O
The ions that make up the H₂O molecule are H⁺ and OH⁻. According to solubility rules, the cation (positively charged ion) is likely to be attracted to an anion (negatively charged ion). Together, they form an ionic bond. This type of bond is when there is a complete transfer of electrons between the two. The Ca²⁺ cation lacks 2 electrons, while the anion OH⁻ has an excess 1 electron. In order to be stable, 1 Ca²⁺ ion and 2 OH⁻ ions must combine.
Therefore, the answer is OH⁻ ion.
That photon's energy is equal to Planck 's constant, multiplied by the light frequency, h is always 6.63* 10^ -34 Joule seconds and the frequency is 6* 10^ 14 Hz.
