Answer: There are 0.00269 moles of acetic acid in buffer.
Explanation:
To calculate the number of moles for given molarity, we use the equation:
.....(1)
Molarity of acetic acid solution = 0.0880 M
Volume of solution = 30.6 mL
Putting values in equation 1, we get:

Thus there are 0.00269 moles of acetic acid in buffer.
Chlorine.
If you search Google images for "Aufbau principle periodic table," you'll find some handy diagrams that will make it much easier to determine an element based on its electron configuration. Determine the number of electrons in the last part of the configuration (in this case, 5), locate that group on the Aufbau periodic table diagram, then count that number from left to right within that group. In this case, within the "3p" portion of the Periodic table, count to 5 and you'll find Chlorine as the answer.
Answer:
hope this helped :( got this from my friend a long time ago but still not sure if it's really correct this
The simple trick which one can consider in such problem where it is asked for positron emission is :
<span>When the atomic number goes DOWN by one and mass number remains unchanged, then a positron is emitted.
</span>
<span>a. </span>

<span>
Here the atomic number decreases by one.
Similarly, options b and d are eliminated.
Option c is also not the answer.
For c, Count the atomic number on left side and compare it with right side. You will see it is 9 on left and 8 on right. Atomic no. did go down by 1. But the atomic mass is changed as well.
</span>
Answer:
Mole fraction of
= 0.58
Mole fraction of
= 0.42
Explanation:
Let the mass of
and
= x g
Molar mass of
= 33.035 g/mol
The formula for the calculation of moles is shown below:
Thus,
Molar mass of
= 46.07 g/mol
Thus,
So, according to definition of mole fraction:

Mole fraction of
= 1 - 0.58 = 0.42