Answer:
(1) -12 Kcal/mol
Explanation:
Our answer options for this question are:
(1) -12 Kcal/mol
(2) -13 Kcal/mol
(3) -15 Kcal/mol
(4) -16 Kcal/mol
With this in mind, we can start with the chemical reaction (Figure 1). In this reaction, <u>two bonds are broken</u>, a C-H and a Br-Br. Additionally, a C-Br and a H-Br are <u>formed</u>.
If we want to calculate the enthalpy value, we can use the equation:
<u>ΔH=ΔHbonds broken-ΔHbonds formed</u>
If we use the energy values reported, its possible to calculate the energy for each set of bonds:
<u>ΔHbonds broken</u>
<u />
C-H = 94.5 Kcal/mol
Br-Br = 51.5 Kcal/mol
Therefore:
105 Kcal/mol + 53.5 Kcal/mol = 146 Kcal/mol
<u>ΔHbonds formed</u>
C-Br = 70.5 Kcal/mol
H-Br = 87.5 Kcal/mol
Therefore:
70.5 Kcal/mol + 87.5 Kcal/mol = 158 Kcal/mol
<u>ΔH of reaction</u>
<u />
ΔH=ΔHbonds broken-ΔHbonds formed=(146-158) Kcal/mol = -12 Kcal/mol
I hope it helps!
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The answer is it shifts right. This could be explained by Le
Chatelier's principle. It states that that when a system experiences a commotion
(such as absorption, temperature, or heaviness variations), it will answer to reinstate
a new equilibrium state. This just means that if there is an energy added, the
reaction is trying to remove it again by going to the right.
D there is one kind of cell of which all living things are made
The earth's plates usually move in three different ways resulting in three different types of plate margins/ boundaries:
CONVERGENT, DIVERGENT and TRANSFORM plate boundaries.When plates move towards each other, they collide and this usually either results in the denser of the plates sliding below the other plate or both plates pushing against each other resulting in both plates being pushed upwards to form often times Fold Mountains. This type of earth tectonics causes a CONVERGENT (destructive; because the collision of the plates results in loss of earth surface area) plate boundary to be formed.
Plates can also pull away from each other and in so doing creating space usually in the form of a fissure between the two moving plates. This fissure usually also for molten earth (magma) rising to the surface and closing the opening between the plates. This type of earth tectonic is known to form DIVERGENT (constructive; because it usually results in new land being formed) plate margins.
Plates also slide against each other (side to side) thus not resulting in neither the destruction or creation of new land. This kind of plate margin is known as the TRANSFORM plate boundary.
The diagram below helps to solidify the points made above.
