Answer:
pKa = 3.675
Explanation:
∴ <em>C</em> X-281 = 0.079 M
∴ pH = 2.40
let X-281 a weak acid ( HA ):
∴ HA ↔ H+ + A-
⇒ Ka = [H+] * [A-] / [HA]
mass balance:
⇒<em> C</em> HA = 0.079 M = [HA] + [A-]
⇒ [HA] = 0.079 - [A-]
charge balance:
⇒ [H+] = [A-] + [OH-]... [OH-] is negligible; it comes from to water
⇒ [H+] = [A-]
∴ pH = - log [H+] = 2.40
⇒ [H+] = 3.981 E-3 M
replacing in Ka:
⇒ Ka = [H+]² / ( 0.079 - [H+] )
⇒ Ka = ( 3.981 E-3 )² / ( 0.079 - 3.981 E-3 )
⇒ Ka = 2.113 E-4
⇒ pKa = - Log ( 2.113 E-4 )
⇒ pKa = 3.675
Chemists have developed insulation.
Answer:
the answer is D) 23 carbon atoms, 34 hydrogen atoms, and 2 oxygen atoms
Explanation:
i took the test and got a 100%

Y is Po-218.
<h3>Explanation </h3>

Here's the symbol of a particle in a nuclear reaction.
.
A stands for mass number. Z stands for atomic number. Both numbers shall conserve in a nuclear reaction.
- The mass number on the left hand side is 222.
- The two mass numbers on the right hand side add up to A + 4.
- 222 = A + 4.
- A = 218
So is the case for the atomic number. Try figure out the atomic number of Y using the same approach.
- The atomic number on the left hand side is 86.
- The two atomic number on the right hand side add up to __ + __.
- 86 = __ + __.
- Z = 84.
What element is Y? The atomic number of Y is 84. Refer to a periodic table. Element 84 corresponds to Po (polonium). Y is Polonium-218. The symbol of Y should be written as
. Hence the equation:
.
Answer:
<em>T</em><em>h</em><em>e</em><em> </em><em>c</em><em>o</em><em>r</em><em>r</em><em>e</em><em>c</em><em>t</em><em> </em><em>a</em><em>n</em><em>s</em><em>w</em><em>e</em><em>r</em><em> </em><em>i</em><em>s</em><em> </em>
Explanation:
<em><u>h</u></em><em><u>o</u></em><em><u>p</u></em><em><u>e</u></em><em><u> </u></em><em><u>t</u></em><em><u>h</u></em><em><u>i</u></em><em><u>s</u></em><em><u> </u></em><em><u>h</u></em><em><u>e</u></em><em><u>l</u></em><em><u>p</u></em><em><u>s</u></em><em><u> </u></em><em><u>u</u></em><em><u>!</u></em><em><u>!</u></em>