Answer:
2.765amu is the contribution of the X-19 isotope to the weighted average
Explanation:
The average molar mass is defined as the sum of the molar mass of each isotope times its abundance. For the unknown element X that has 2 isotopes the weighted average is defined as:
X = Mass X-19 * Abundance X-19 + MassX-21 * Abundance X-21
The contribution of the X-19 isotope is its mass (19.00 amu) times its abundance (14.55% = 0.1455). That is:
19.00amu * 0.1455 =
2.765amu is the contribution of the X-19 isotope to the weighted average
The number of moles present in 29.5 grams of argon is 0.74 mole.
The atomic mass of argon is given as;
Ar = 39.95 g/mole
The number of moles present in 29.5 grams of argon is calculated as follows;
39.95 g ------------------------------- 1 mole
29.5 g ------------------------------ ?
Thus, the number of moles present in 29.5 grams of argon is 0.74 mole.
<em>"Your question seems to be missing the correct symbol for the element" </em>
Argon = Ar
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Answer:
- <em>(B.) The pH of a buffer solution is determined by the ratio of the concentration of conjugate base to the concentration of strong acid.</em>
- <em>(C.) A buffer is generally made up of a weak acid and its conjugate base. </em>
- <em>(D.) The pH of a buffer solution does not change significantly when any amount of a strong acid is added.</em>
Explanation:
A buffer is solution which resists change in pH upon addition of either acids or bases.
The pH of a buffer is calculated by the ratio of the concentration of base to concentration of acid. The weak acid and conjugate base have a Ka similar to the pH desired.
Answer:
the second one looks like it so I picked the second one
Answer:
for what I can see in the picture the volume is 155
Explanation:
