Answer:
0.00840
Explanation:
The computation of the mole fraction is as follow:
As we know that
Molar mass = Number of grams ÷ number of moles
Or
number of moles = Number of grams ÷ molar mass
Given that
Number of moles of CaI2 = 0.400
And, Molar mass of water = 18.0 g/mol
Now Number of moles of water is
= 850.0 g ÷ 18.0 g/mol
= 47.22 mol
And, Total number of moles is
= 0.400 + 47.22
= 47.62
So, Molar fraction of CaI2 is
= 0.400 ÷ 47.62
= 0.00840
Answer:
Sc (Scandium) has the given electronic configuration.
Explanation:
The given electronic configuration is [Ar]
.
The last electron enters the d-subshell and hence is a d-block element known as Scandium with chemical symbol Sc.
For 4s subshell
n=4,l=0 and m ranges from -l to +l so m=0.
For 3d subshell
n=3,l=2 and m ranges from -l to +l so m can take values -2,-1,0,+1,+2
Note:
l values for subshells:
s : 0
p : 1
d : 2
f : 3 and so on.
To take the percent by mass of this element, we use the
formula:
% mass = (mass of element / mass of ore) * 100%
% mass = (47.5 g / (660 kg * 1000 g / kg)) * 100*
<span>% mass = 7.20 x 10^-3 %</span>
True, both of the red and white phosphorus is a pure substance.
Both red and white phosphorus is made of phosphor element but they have a different structure which causes them to have a different color. This phenomenon called allotropes when a chemical element has two or more different form.They are not compounds as they are only made of phosphorus. A compound should be made by at least two different elements.
Answer: 100 grams of glucose represents 0.55 moles .
Explanation:
