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:
See explanation
Explanation:
1) Physical change is usually reversible, while chemical change isn't
2) Chemical change involves the change of chemical composition of matter while physical change doesn't
Answer:
False
Explanation:
Cell division is a primary procedure by all cells. This process in the life cycle of cells ensures that new cells (daughter cells) are produced. The two major process are; meiosis and mitosis.
Normal cells would divide if the nutrients required are not present, since water is the main nutrient required. But in some cases, the division process may lead to an effect on one or both daughter cells. This effect is called mutation, thereby mutated cells may be produced.
Answer:
Reforestation can be used to undo and rectify the effects of deforestation and improve the quality of human life by absorbing pollution and dust from the air, rebuilding natural habitats and ecosystems,reducing global warming via biosequestration of atmospheric carbon dioxide, and harvesting for resources, particularly.
Explanation:
Answer:
True
Explanation:
Depends of the size and comparison