<span> First you need to know how many isotopes there are of silicon, and its average atomic units (look at periodic table). Then make up a system of equations to solve for it. Theres 3 stable silicon isotopes (28, 29, 30) so you will need to have 3 equations. You must be given the percent abundance of at least one of the isotopes to solve because here I can only see 2 equations (numbered down below) set x = percent abundance of si-28 y = percent abundance of si-29 z = percent abundance of si-30 since all of silicon atoms account for 100% of all silicon: x + y + z = 100% = 1 therefore: 1) x = 1 - y - z You also have 2) 28x + 29y + 30z = average atomic mass you can substitute x so that equation becomes: 28 (1 - y - z) + 29y + 30z = average atomic mass See how you have 2 variables here? You cant go on until you know the value of one isotope already or you have given a clue which you can derive the third equation</span>
Cycloalkanes are those saturated organic compounds which exist in the form of Rings. Their Hydrogen Deficiency Index in one. The General formula for cycloalkanes is,
CnH2n
When number of Carbons = 8
Then
C₈H₂₍₈₎
C₈H₁₆
Result:
Cycloalkane containing 8 carbon atoms has
16 hydrogen atoms.
A. Oxygen. Oxygen has an atomic mass of 16. The atomic mass of an atom is the combined weight o the protons and neutrons. Since Oxygen's atomic mass is 16, it has 8 protons and 8 neutrons.
Yes because the protons are the same but the neutrons change
Answer:
35.1 kJ/mol is the expected value for the heat of sublimation of acetic acid.
Explanation:
..[1]
Heat of vaporization of acetic acid = 
..[2]
Heat of fusion of acetic acid = 
Heat of sublimation of acetic acid = 
..[3]
[1] + [2] = [3] (Hess's law)


35.1 kJ/mol is the expected value for the heat of sublimation of acetic acid.