Answer:
0,07448M of phosphate buffer
Explanation:
sodium monohydrogenphosphate (Na₂HP) and sodium dihydrogenphosphate (NaH₂P) react with HCl thus:
Na₂HP + HCl ⇄ NaH₂P + NaCl <em>(1)</em>
NaH₂P + HCl ⇄ H₃P + NaCl <em>(2)</em>
The first endpoint is due the reaction (1), When all phosphate buffer is as NaH₂P form, begins the second reaction. That means that the second endpoint is due the total concentration of phosphate that is obtained thus:
0,01862L of HCl×
= 1,862x10⁻³moles of HCl ≡ moles of phosphate buffer.
The concentration is:
= <em>0,07448M of phosphate buffer</em>
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I hope it helps!
Answer:
Increasing the pressure on a reaction involving reacting gases increases the rate of reaction. Changing the pressure on a reaction which involves only solids or liquids has no effect on the rate.
Explanation:
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PLEASE MARK BRAINLIEST!</u></h2>
It is believed that, 66 million years ago, the first human lived. This is according to fossil. It is thought that, after the Cretaceous–Paleogene extinction [the extinction of dinosaurs and 3/4 of plant and animal life], the first humans appeared.
I hope this helps!
Answer:
This is the electronic configuration of selenium atom.
Explanation:
Selenium is present in group 16.
It is the member of oxygen family.
Its atomic number is 34.
Electronic configuration:
Se₃₄ = 1s² 2s² 2p⁶ 3s² 3p⁶ 4s² 3d¹⁰ 4p⁴
The noble gas notation is used for the shortest electronic configuration of other periodic table elements.
For example:
The atomic number of Argon is 18, and its electronic configuration is,
Ar₁₈ = 1s² 2s² 2p⁶ 3s² 3p⁶
Abbreviated electronic configuration:
Se₃₄ = [Ar] 4s² 3d¹⁰ 4p⁴
I think the answer for this question is
B. 9(1-x)
