The benzene molecule has the molecular formula C6H6
.
Sometimes it is represented as a molecule with three doble bonds and three single bonds. But that does not count for the fact that experimentally all the bonds are equal: same length and same strength.
The six carbon bonds are equal because there is not preference for the valence electrons to attach to one or othe neighbor carbon, so at the electrons delocalize inside the molecules and form a uniform cloud around the six carbon atoms.
This is the effect named resonance and thas is why the molecule of benzene instead of being represented with some three single bonds and three doble bonds is represented with a circle (a ring) inside the molecule which represents an intermediate kind of bond shares by all the carbon atoms.
This structure was discovered (literally dreames as some texts tell) by Kekulé.
Answer:
The correct answer is B. Line Graphs
Explanation:
The chemical reaction would be expressed as follows:
HBr + LiOH = LiBr + H2O
We are given the volumes and corresponding concentration to be used for the reaction. We use these values to solve for the concentration of the other reactant. We do as follows:
0.253 mol LiOH / L solution ( 0.01673 L ) ( 1 mol HBr / 1 mol LiOH ) = 0.00423 HBr needed
Concentration of HBr =0.00423mol / .010 L = 0.423 M HBr
The activation energy Ea can be related to rate constant (k) at temperature (T) through the equation:
ln(k2/k1) = Ea/R[1/T1 - 1/T2]
where :
k1 is the rate constant at temperature T1
k2 is the rate constant at temperature T2
R = gas constant = 8.314 J/K-mol
Given data:
k1 = 0.543 s-1; T1 = 25 C = 25+273 = 298 K
k2 = 6.47 s-1; T = 47 C = 47+273 = 320 K
ln(6.47/0.543) = Ea/8.314 [1/298 - 1/320]
2.478 = 2.774 *10^-5 Ea
Ea = 0.8934*10^5 J = 89.3 kJ
The answer is Ra
Atomic number for Be is 4
Atomic number for Mg 12
Atomic number for Ra 88
Atomic number for Ba 56