Activation energy is a thermodynamic barrier that must be overcome before products are formed in a reaction. It is the minimum amount of energy needed for a reaction to occur. The energy can be in the form of kinetic or potential energy. This concept was introduced by Svante Arrhenius, which brought about the Arrhenius equation which is a formula used to determine rate of reactions.
Answer:
Explanation:
(a) Answer: Intermolecular forces
The reason for this answer is because the substance (paraffin wax) only changed it's state from solid to liquid and didn't undergo a breakage in it's covalent bond within it's carbon chain which would have produced another substance.
(b) Solid substances are generally more dense than there corresponding liquid substances because the more compact particles are (which occurs in solids), the more dense they become. They are thus more dense than liquids because liquids have there particles loosely packed and well spaced making them less dense than there corresponding solids. Hence, the solid paraffin wax was going to become less dense because it's particles moved from being tightly packed (as solids) to being loosely packed (as liquids). Density refers to mass per volume but can also be described as the level of compactness of a substance. Thus, since liquid is not as compact as solid, it can be said to be less dense than solids.
Answer:
Explanation has been given below.
Explanation:
- Chloroform has three polar C-Cl bonds. Methylene chloride has two polar C-Cl bonds. So it is expected that chloroform should be more polar and posses higher dipole moment than methylene chloride.
- Two factors are liable for the opposite trend observed in dipole moments of methylene chloride and chloroform.
- First one is the number of hyperconjugative hydrogen atoms present in a molecule. Hyperconjugation occurs with vacant d-orbital of Cl atom. Hyperconjugation amplifies charge separation in a molecule resulting higher dipole moment.
- Methylene chloride has two hyperconjugative hydrogen atoms and chloroform has one hyperconjugative hydrogen atom.Therefore methylene chloride should have higher charge separation as compared to chloroform.
- Second one is induction of opposite polarity in a C-Cl bond by another C-Cl bond in a molecule. Higher the opposite induction of polarity, lower the charge separation in a molecule and hence lower the dipole moment of a molecule.
- Chloroform has three C-Cl bonds and methylene chloride has two C-Cl bonds. Therefore opposite induction is higher for chloroform resulting it's lower dipole moment.
Answer:
See Explanation
Explanation:
Let us consider the first two reactions, the initial concentration of CO was held constant and the concentration of Hbn was doubled.
2.68 * 10^-3/1.34 * 10^-3 = 6.24 * 10^-4/3.12 * 10^-4
2^1 = 2^1
The rate of reaction is first order with respect to Hbn
Let us consider the third and fourth reactions. The concentration of Hbn is held constant and that of CO was tripled.
1.5 * 10^-3/5 * 10^-4 = 1.872 * 10^-3/6.24 * 10^-4
3^1 = 3^1
The reaction is also first order with respect to CO
b) The overall order of reaction is 1 + 1=2
c) The rate equation is;
Rate = k [CO] [Hbn]
d) 3.12 * 10^-4 = k [5 * 10^-4] [1.34 * 10^-3]
k = 3.12 * 10^-4 /[5 * 10^-4] [1.34 * 10^-3]
k = 3.12 * 10^-4/6.7 * 10^-7
k = 4.7 * 10^2 mmol-1 L s-1
e) The reaction occurs in one step because;
1) The rate law agrees with the experimental data.
2) The sum of the order of reaction of each specie in the rate law gives the overall order of reaction.
