Answer:
<h2>0.62 moles</h2>
Explanation:
To find the number of moles in a substance given it's number of entities we use the formula
where n is the number of moles
N is the number of entities
L is the Avogadro's constant which is
6.02 × 10²³ entities
From the question we have
We have the final answer as
<h3>0.62 moles</h3>
Hope this helps you
Cl is stable as a diatomic molecule where the 2 Cl atoms are held together by a covalent bond
molar mass of the diatomic molecule is 70.9 g/mol
therefore 70.9 g of Cl₂ is - 1 mol
then 140 g of Cl₂ is - 1/70.9 x 140 = 1.97 mol
there are 1.97 mol of Cl₂ present
Answer:
The mole fraction of NaOH in an aqueous solution that contain 22.9% NaOH by mass=0.882
Explanation:
We are given that
Aqueous solution that contains 22.9% NaOH by mass means
22.9 g NaOH in 100 g solution.
Mass of NaOH(WB)=22.9 g
Mass of water =100-22.9=77.1
Na=23
O=16
H=1.01
Molar mass of NaOH(MB)=23+16+1.01=40.01
Number of moles =
Using the formula
Number of moles of NaOH
Molar mass of water=16+2(1.01)=18.02g
Number of moles of water
Now, mole fraction of NaOH
=
=0.882
Hence, the mole fraction of NaOH in an aqueous solution that contain 22.9% NaOH by mass=0.882
The easiest way to approximate ph level is through the ph paper measurement system because using pH paper would be best for doing a quick measurement in the field. It does not essentially need to be calibrated or standardized and the papers make available an instant estimate.