Answer:
1.88 x 10²³molecules of H₂O
Explanation:
Given parameters:
Mass of H₂O = 5.609g
Unknown:
Number of molecules of H₂O = ?
Solution:
To solve this problem, we need to find the number of moles of given compound first.
Number of moles =
Molar mass of H₂O = 2(1) + 16 = 18g/mol
Number of moles = = 0.31mole
From mole concept;
1 mole of a substance contains 6.02 x 10²³molecules
0.31 mole of H₂O will therefore contain 0.31 x 6.02 x 10²³molecules
= 1.88 x 10²³molecules of H₂O
<u>Answer: </u>The molar mass of the metal is 96.45 g/mol
<u>Explanation:</u>
The fluoride of the metal formed is
The oxidation half-reaction follows:
Calculating the theoretical mass deposited by using Faraday's law, which is:
......(1)
where,
m = actual mass deposited = 1.25 g
M = molar mass of metal = ?
I = average current = 3.86 A
t = time period in seconds = 16.2 min = 972 s (Conversion factor: 1 min = 60 sec)
n = number of electrons exchanged =
F = Faraday's constant = 96500 C
Putting values in equation 1, we get:
Hence, the molar mass of the metal is 96.45 g/mol