Hello!
First you need to calculate q
<span>delta U is change in internal energy </span>
<span>delta U = q + w </span>
<span>q is heat and w work done </span>
<span>here work was done by the system means energy leaving the system so w is negative </span>
<span>delta U = q + w </span>
<span>q = delta U - w = 6865 J - (-346 J) = 7211 J = 7.211 KJ </span>
<span>q = m x c x delta T </span>
<span>7211 J = 80.0 g x c x (225-25) °C </span>
<span>c = 0.451 J /g °C
</span>
Hope this Helps! Have A Wonderful Day! :)
Scirnce uses a method of testing to declare rules or facts. myth and fairy tales have no way of being tested. cats are a physical creature we can see, test, and observe. a mythical idea canny be tested. for example: mermaids cannot be tested as we have none to observe.
43.8 kJ
<h3>
Explanation</h3>
There are two electrodes in a voltaic cell. Which one is the anode?
The lithium atom used to have no oxygen atoms when it was on the reactant side. It gains two oxygen atoms after the reaction. It has gained more oxygen atoms than the manganese atom. Gaining oxygen is oxidation. As a result, lithium is being oxidized.
Oxidation takes place at the anode of a cell. Therefore, the anode of this cell is made of lithium.
Lithium has an atomic mass of 6.94. Each gram of Li would contain 1/6.94 = 0.144 moles of Li atoms. Each Li atom loses one electron in this cell. Therefore, the number of electron transferred, <em>n</em>, equals 0.144 moles for each gram of the anode.
Let
represents the electrical energy produced.
, where
- <em>n</em> is the <em>number of moles</em> electrons transferred,
- <em>F</em> is the Faraday's constant,
- <em>E</em>
is the cell potential,
<em>n </em>= 0.144 mol, as shown above, and
<em>F </em>= 96.486 kJ / (
).
Therefore,
.
Answer:
![r_{H_2} = \frac{-1}{2} r_{HI}](https://tex.z-dn.net/?f=r_%7BH_2%7D%20%3D%20%5Cfrac%7B-1%7D%7B2%7D%20r_%7BHI%7D)
Explanation:
Hello!
In this case, considering the given chemical reaction:
![H_2(g) + I_2(g) \rightarrow 2HI(g)](https://tex.z-dn.net/?f=H_2%28g%29%20%2B%20I_2%28g%29%20%5Crightarrow%202HI%28g%29)
Thus, by applying the law of rate proportions, we can write:
![\frac{1}{-1} r_{H_2} = \frac{1}{-1}r_{i_2} = \frac{1}{2} r_{HI}](https://tex.z-dn.net/?f=%5Cfrac%7B1%7D%7B-1%7D%20r_%7BH_2%7D%20%3D%20%5Cfrac%7B1%7D%7B-1%7Dr_%7Bi_2%7D%20%3D%20%5Cfrac%7B1%7D%7B2%7D%20r_%7BHI%7D)
Whereas the stoichiometric coefficients of reactants are negative due their disappearance and that of the product is positive due to its appearance. In such a way, when we relate the rate of disappearance of hydrogen gas to the rate of formation of hydrogen iodide, we obtain:
![r_{H_2} = \frac{-1}{2} r_{HI}](https://tex.z-dn.net/?f=r_%7BH_2%7D%20%3D%20%5Cfrac%7B-1%7D%7B2%7D%20r_%7BHI%7D)
Best regards!
Answer: <span>The molecules of a substance which must have the
<u>a</u></span>
<u>bility to move past one another</u> are said to be flexible.
Explanation: Those substances are said to be flexible which can be
bent without breaking. There are many substances which are
hard in nature but still can be bent. The hardness of such materials is due to
strong interactions between the molecules and the flexibility comes due to their
amorphous backbone. Therefore, greater the
crystalline level of macromolecules lesser is the flexibility and greater the amorphous character greater is the flexibility and vice versa. Also, the flexibility of polymers is increased by adding
plastisizers in it. Plastisizers make the hard polymers flexible by breaking the crosslinkers and enabling the macromolecules to move past one another.