Calculate molar mass first and then calculate moles using this formula:
Moles=given mass/ molr mass
Answer:
D) 10.812
Explanation:
Given:
The two isotopes of boron (B).
Boron-10 has an abundance of 19.8% and Boron -11 has an abundance of 80.2%
To find:
The atomic mass of europium.
Solution:
Mass of Boron-10 = 10.013 amu
The percentage abundance of Boron-10 = 19.8%
The fractional abundance of Boron-10 =0.198
Mass of Boron-11 = 11.009 amu
The percentage abundance of Boron-11= 80.2%
The fractional abundance of Boron-11= 0.802
The average atomic mass of Boron = A.M
A.M = Mass of isotope x Fractional abundance of isotope
= 10.013amu x 0.198 +11.009amu x 0.802 = 10.81u
Therefore, D) 10.812 amu is the atomic mass of boron.
I would go with D. Oxygen is released as a gas after water is spilt.
This may not be right.
I hope this helps!
Have a Good Afternoon!
Best of Luck!
Answer:
The UK is mostly under the influence of the maritime polar air mass from the north-west. The south and south-east of England are the least exposed to polar air masses from the north-west, and on occasion see continental tropical air masses from the south, which bring warm dry air in the summer.
Explanation:
The UK has a temperate climate. In general, this means that Britain gets cool, wet winters and warm, wet summers. London, in the south-east of the UK, is a region characterised by a warm and dry climate in the summer and a cold and dry climate in the winter.
According to Boltzmann reaction entropy difference between two states is given by ΔS and is equal to 5.76 .
According to Boltzmann Reaction:
S= kB lnW
Where,
W is number of Arrangements possible
Now ,
ΔS = S(final) - S(initial)
S(initial) = kBln1 (Since only one arrangement is possible)
= 0
Again,
S(final) = kBln2^n
Now,
As A-B can exist as A-B or B-A .
Hence, two arrangements are possible and since 1 mole of species .
Hence, 2^n
S(final) = N kB ln2
=R ln 2
= 8.314 ×2.303× log 2
Hence,
S(final) = 5.76
ΔS = 5.76 -0
=5.76
Thus, from the above conclusion we can say that, according to Boltzmann reaction entropy difference between two states is given by ΔS and is equal to 5.76 .
Learn more about Entropy here : brainly.com/question/17241209
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