Hey there!:
HA <=> H⁺ + A⁻
pH = -log[H+] = 6
[ H⁺ ] = 10^-pH
[ H⁺] = 10 ^ -6
[ H⁺ ] = 0.000001 M
Percent dissociation:
[ H⁺ ] / [ HA]o * 100
[ 0.000001 / 0.10 ] * 100
0.00001 * 100 => 0.0010%
Answer D
Hope that helps!
1) Answer: A hot pack feels warm when chemicals in it combine.
Explanation: Reactions or process in which heat is released(produced) are known as exothermic reactions or process and those in which the heat is absorbed are known as endothermic reactions or process.
If a beaker feels cools when chemical in it react then it means the chemicals have absorbed the heat energy from its surroundings and so it is an example of an endothermic process.
A hot pack feels warm when chemicals in it combine means the energy is released in the chemical reaction and so it is an example of an exothermic process.
Plants use the sun's energy for photosynthesis which is a process of forming food for the plants. Energy acts as a reactant in this process and so it is an example of endothermic process.
Frying an egg by heating it on a stove is an example of an endothermic process as the heat is required to fry the egg.
So, the only exothermic process is the second one, "A hot pack feels warm when chemicals in it combine."
2) In the given equation, heat is written as a product means the heat is released in the equation and so it is an example of an exothermic reaction.
So, the correct choice is the last one " It is exothermic because energy is released."
Answer:
68,2%
Explanation:
Supposing the initial salt concentration of lake Parsons is the same of non-isolated lakes, 6,67L, and the change of salt concentration in isolated lake is just for water evaporation it is possible to write:
6,67gL⁻¹×X = 21gL⁻¹×Y
<em>-Where X is the initial water and Y is the water that remains in the isolated lake-</em>
Thus:
6,67X = 21Y
0,318 = Y/X
0,318 is the ratio of water that remains between total water. To obtain the ratio of evaporated water:
1-0,318 = 0,682
In percentage: <em>68,2%</em>
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I hope it helps!
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It makes sense that an inner shell electron would be tougher to remove
than a valence electron because the inner shell electron is closer to
the positive nucleus of the atom. Seeing as an electron caries a
negative charge it would be too attracted to the positive core to leave
readily. Also, the inner shell electrons are constantly repelling
electrons outside of it's energy level (however the reason these
electrons outside innershell energy levels don't simply fly away is the
charge of the positive core overcomes the smaller charges of the
comparably negligible inner shell electrons, but that repulsion is still
there so keep that in mind) </span>
C. chlorophyll
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