H2(g) +C2H4(g)→C2H6(g)
H-H +H2C =CH2→H3C-Ch3
2C -H bonds and one C-C bond are formed while enthalpy change (dH) of the reaction,
H-H: 432kJ/mol
C=C: 614kJ/mol
C-C: 413 kJ/mol
C-C: 347 kJ/mol
dH is equal to sum of the energies released during the formation of new bonds or negative sign, and sum of energies required to break old bonds or positive sign.
The bond which breaks energy is positive.
432+614 =1046kJ/mol
Formation of bond energy is negative
2(413) + 347 = 1173 kJ/mol
dH reaction is -1173 + 1046 =-127kJ/mol
Answer:
2.5
Explanation:
The given costs for the purchase and delivery of the cupcakes are;
The cost of 10 cupcakes and the delivery fee = $30
The cost of 25 cupcakes and the delivery fee = $67.50
Let 'c' represent the fixed cost of delivery of the cup cakes, and let 'x' represent the cost of each cup cake, we have;
30 = 10·x + c...(1)
67.50 = 25·x + c...(2)
Subtracting equation (1) from equation (2) gives;
67.50 - 30 = 37.50 = 25·x - 10·x + c - c = 15·x
∴ x = 37.50/15 = 2.5
The cost of each cupcake, x = 2.5
(∴ The delivery fee = 30 - 10 × 2.5 = 5)
The cost of each cupcake is 2.5.
Elapsed time
Time Graphs. Set the Type of graph menu to position vs. time and the Choose a graph menu to position graph 1. This means that the vertical axis represents the position, or location, of the caterpillar along the ground, while the horizontal axis represents the elapsed time.
Either give off or gain electrons to make a total of 8
Answer:
Electrical Energy
Explanation:
Batteries store chemical energy and change it to electrical energy.