Benzene is the simplest example of the aromatic compound
Firstly, we want to explain what is the meaning of aromaticity?
the aromaticity is called on any compound which has cyclic shape and has a resonance. Resonance is delocalization of the electrons (which form the double bond) in the molecules, in other words, the double bond moves through the compound by the movement of electrons which leads to increasing the stability of the compound by this process which called resonance. The resonance may occur in open or cyclic compounds, and if it occurs in cyclic compounds, these compounds are called aromatic compounds. So, the benzene considered to be the simplest aromatic compound where it is not only has a resonance in a cyclic ring but also it was the first aromatic compound discovered and also, the most common aromatic compounds are derivatives of it (benzene).
0.52kg = 520g
520g x 0.35 = 182g
182 x 6.022x10^23 = 1.096004E26
1.096004E26 / 107.8 = 1.0167012987E24 atoms
Answer:
7.14%
Explanation:
From the question,
percentage by mass hydrogen in C₄H₈O₃ (h) = mass of hydrogen present in C₄H₈O₃(m)/molar mass of C₄H₈O₃ (m')
h = (m'/m)×100..................... Equation 1
Given: m' = (14×4)+(1×8)+(16×3) = 56+8+48 = 112 g, m = (1×8) = 8 g
Substitute these values into equation 1
h = (8/112)×100
h = 7.14%.
Hence the percentage of hydrogen in 70 g of C₄H₈O₃ is 7.14%
The reaction for the formation of MgO(s):
2 Mg (s) + O2(g) -à
2MgO(s) ΔH = -601.24
kJ/mol
<span>The enthalpy
information is taken from: http://webbook.nist.gov/cgi/inchi?ID=C1309484&Mask=2</span>
From the equation and with an enthalpy change of -231 kJ:
-231 kJ * 2 mol Mg * (1/-601.24 kJ/mol) = 0.76841 mol Mg
Then, with the molar mass of MgO = 40.3,
0.76841 mol Mg *(2 mol MgO/2 mol Mg)* 40.3 g/mol MgO = <span>30.967 g MgO</span>