Answer:
pH = 1.32
Explanation:
H₂M + KOH ------------------------ HM⁻ + H₂O + K⁺
This problem involves a weak diprotic acid which we can solve by realizing they amount to buffer solutions. In the first deprotonation if all the acid is not consumed we will have an equilibrium of a wak acid and its weak conjugate base. Lets see:
So first calculate the moles reacted and produced:
n H₂M = 0.864 g/mol x 1 mol/ 116.072 g = 0.074 mol H₂M
54 mL x 1L / 1000 mL x 0. 0.276 moles/L = 0.015 mol KOH
it is clear that the maleic acid will not be completely consumed, hence treat it as an equilibrium problem of a buffer solution.
moles H₂M left = 0.074 - 0.015 = 0.059
moles HM⁻ produced = 0.015
Using the Henderson - Hasselbach equation to solve for pH:
ph = pKₐ + log ( HM⁻/ HA) = 1.92 + log ( 0.015 / 0.059) = 1.325
Notes: In the HH equation we used the moles of the species since the volume is the same and they will cancel out in the quotient.
For polyprotic acids the second or third deprotonation contribution to the pH when there is still unreacted acid ( Maleic in this case) unreacted.
Answer:
To have the electronic configuration equal to 1s²2s²2p⁶3s²3p⁶4s²3d⁷, the chemical element must have an electrical charge equal to 27, that is, it must have 27 electrons, such as Cobalt (Co), for example.
Explanation:
The electronic configuration shown in the question above is known as the Linus Pauling distribution and represents the energy sub-levels that an electrically charged atom can have in relation to the amount of electrons it has.
The layers sub-levels are presented in the following order 1s² 2s² 2p⁶ 3s² 3p⁶ 4s² 3d¹º 4p⁶ 5s² 4d¹º 5p⁶ 6s² 4f14 5d¹º 6p⁶ 7s² 5f14 6d¹º 7p⁶. Where the small numbers represent the number of electrons in each sub-level and the large numbers represent the layers of electronic distribution.
Accordingly, we can see that an atom that has the configuration 1s²2s²2p⁶3s²3p⁶4s²3d⁷ has 27 electrons, like Cobalt.
Answer:
the number of protons and neutrons at both terminals are equal
Explanation:
When the number of positive charge and negative charge are both equally the terminal, it becomes neutral and out of charge, because first it undergo enough chemical reaction and there is no remaining tendency for positive and negative charges to get separated. When this tendency dies, the battery also will run out of charge.
No, darker colors like purple and blue have higher wave frequency which transmit more energy.