Answer:-
(a) 3.5
(b) 3
Explanation:-
2KClO3 --> 2KCl + 3 O2
From the equation we see that 2 moles of KClO3 gives 2 moles of KCl.
So 3.5 moles of KClO3 will give 3 moles of KCl.
Again
3 moles of O2 are produced with 2 moles of KCl.
If 4.5 moles of O2 produced then
moles of KCl = 4.5 x 2/3
=3
Answer : The mole fraction of NaCl in a mixture is, 0.360
Explanation : Given,
Moles of 
= 7.21 mole
Moles of 
= 9.37 mole
Moles of 
= 3.42 mole
Now we have to calculate the mole fraction of .
Now put all the given values in this formula, we get:
Therefore, the mole fraction of NaCl in a mixture is, 0.360
Answer:
a. because it is an element
Explanation:
its pure because it only has one type of atom, making it an element
Answer:
0.550
Explanation:
The absorbance (A) of a substance depends on its concentration (c) according to Beer-Lambert law.
A = ε . <em>l</em> . c
where,
ε: absorptivity of the species
<em>l</em>: optical path length
A 45 mM phosphate solution (solution A) had an absorbance of 1.012.
A = ε . <em>l</em> . c
1.012 = ε . <em>l</em> . 45 mM
ε . <em>l</em> = 0.022 mM⁻¹
We can find the concentration of the second solution using the dilution rule.
C₁ . V₁ = C₂ . V₂
45mM . 11mL = C₂ . 20.0 mL
C₂ = 25 mM
The absorbance of the second solution is:
A = (ε . <em>l</em> ). c
A = (0.022 mM⁻¹) . 25 mM = 0.55 (rounding off to 3 significant figures = 0.550)
