Answer: 30.27 g
Explanation:
Since the silver is in units of atoms, we have to use Avogadro's number and molar mass.
Avogadro's number: 6.022×10²³ atoms/mol
Molar Mass: 107.87 g/mol
Now that we have everything we need, we can convert atoms to grams.
Answer:
151.94 u
Explanation:
The atomic mass of Eu is the <em>weighted average</em> of the atomic masses of its isotopes.
We multiply the atomic mass of each isotope by a number representing its relative importance (i.e., its <em>percent abundance</em>).
The atomic masses of Eu-151 and Eu-153 are 150.92 u and 152.92 u, respectively.
Set up a table for easy calculation.
0.4803 × 150.92 u = 72.472 u
0.5197 × 152.92 u = <u> 79.473 u
</u>
TOTAL = 151.94 u
Answer:
Concentration: 0.185M HX
Ka = 9.836x10⁻⁶
pKa = 5.01
Explanation:
A weak acid, HX, reacts with NaOH as follows:
HX + NaOH → NaX + H2O
<em>Where 1 mole of HX reacts with 1 mole of NaOH</em>
To solve this question we need to find the moles of NaOH at equivalence point (Were moles HX = Moles NaOH).
18.50mL = 0.01850L * (0.20mol / L) = 0.00370 moles NaOH = Moles HX
In 20.0mL = 0.0200L =
0.00370 moles HX / 0.0200L = 0.185M HX
The equilibrium of HX is:
HX(aq) ⇄ H⁺(aq) + X⁻(aq)
And Ka is defined as:
Ka = [H⁺] [X⁻] / [HX]
<em>Where [H⁺] = [X⁻] because comes from the same equilibrium</em>
As pH = 2.87, [H+] = 10^-pH = 1.349x10⁻³M
Replacing:
Ka = [H⁺] [H⁺] / [HX]
Ka = [1.349x10⁻³M]² / [0.185M]
Ka = 9.836x10⁻⁶
pKa = -log Ka
<h3>pKa = 5.01</h3>
Answer:
The another word for microorganism is microbe
