Answer:
The surface-to-volume ratio of a C-60 fullerene is 3:77.
Explanation:
Surface area of sphere = 
Volume of the sphere = 
where : r = radius of the sphere
Radius of the C-60 fullerene sphere = r = 77 pm
Surface area of the C-60 fullerene = 
...[1]
Volume area of the C-60 fullerene = 
..[2]
Dividing [1] by [2]:
The surface-to-volume ratio of a C-60 fullerene is 3:77.
The 1st law of thermodynamics doesn't specify that matter can be created nor destroyed, but that the total amount of energy in a closed system cannot be created nor destroyed though it can be changed from one form to another.
ΔHrxn = ΣδΗ(bond breaking) - ΣδΗ(bond making)
Bond enthalpies,
N ≡ N ⇒ 945 kJ mol⁻¹
N - Cl ⇒ 192 kJ mol⁻¹
Cl - Cl⇒ 242 kJ mol⁻¹
According to the balanced equation,
ΣδΗ(bond breaking) = N ≡ N x 1 + Cl - Cl x 3
= 945 + 3(242)
= 1671 kJ mol⁻¹
ΣδΗ(bond making) = N - Cl x 3 x 2
= 192 x 6
= 1152 kJ mol⁻¹
δHrxn = ΣδΗ(bond breaking) - ΣδΗ(bond making)
= 1671 kJ mol⁻¹ - 1152 kJ mol⁻¹
= 519 kJ mol⁻¹
Answer:
Groups show similar chemical properties about the elements
Explanation:
The periodic table is divided into groups and periods. Groups are vertical while periods are horizontal.
All elements in the same group possess the same number of outermost shell electrons. This number of outermost shell electrons controls the reactivity of the elements in the group.
Hence, groups show similar chemical properties of the elements in them, Groups separate elements into families which assist in the speedy study of elements.
