B. At the equivalence point of a titration of the [H+] concentration is equal to 7.
<h3>What is equivalence point of a titration?</h3>
The equivalence point of a titration is a point in titration at which the amount of titrant added is just enough to completely neutralize the analyte solution.
At the equivalence point in an acid-base titration, moles of base equals moles of acid and the solution only contains salt and water.
At the equivalence point, equal amounts of H+ and OH- ions combines as shown below;
H⁺ + OH⁻ → H₂O
The pH of resulting solution is 7.0 (neutral).
Thus, the pH at the equivalence point for this titration will always be 7.0.
Learn more about equivalence point here: brainly.com/question/23502649
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The much of the sample that would remain unchanged after 140 seconds is 2.813 g
Explanation
Half life is time taken for the quantity to reduce to half its original value.
if the half life for Scandium is 35 sec, then the number of half life in 140 seconds
=140 sec/ 35 s = 4 half life
Therefore 45 g after first half life = 45 x1/2 =22.5 g
22.5 g after second half life = 22.5 x 1/2 =11.25 g
11.25 g after third half life = 11.25 x 1/2 = 5.625 g
5.625 after fourth half life = 5.625 x 1/2 = 2.813
therefore 2.813 g of Scandium 47 remains unchanged.
Answer : The internal energy change is, -506.3 kJ/mol
Explanation :
Formula used :
or,
where,
= change in enthalpy = 
= change in internal energy = ?
= change in moles
Change in moles = Number of moles of product side - Number of moles of reactant side
According to the reaction:
Change in moles = 0 - 2 = -2 mole
That means, value of 
= 0
R = gas constant = 8.314 J/mol.K
T = temperature = 
Now put all the given values in the above formula, we get
Therefore, the internal energy change is -506.3 kJ/mol
Answer:
their are a it is in the chemicle
Explanation:18 carbon and 4 hydrogen
so it is a toatle of 22 atoms
You are right!! Good job!!!
