Answer:
The significance of "Er" in the diagram is :
B.) Threshold energy for reaction
Explanation:
Threshold energy : It is total amount of energy required by the reactant molecule to reach the transition state .
Activation energy : It is the excess energy absorbed by the molecules to reach the transition state.
<u>Activation Energy = Threshold Energy - Average Kinetic Energy</u>
<u>This means Activation energy decreases on increasing kinetic energy</u>
On increasing Temperature average kinetic energy of the molecule increases which reduces the activation energy and the reaction occur faster in that case.
Catalyst also reduces the Activation energy.
<u>Er = Threshshold energy for reaction at 30 degree</u>
<u>Ea = Activation Energy</u>
<u>The given figure shows that the threshold energy decreases on increasing the temperature</u>
<u>Only the molecule having energy greater than Er can react to form product</u>
Answer:
52 da
Step-by-step explanation:
Whenever a question asks you, "How long to reach a certain concentration?" or something similar, you must use the appropriate integrated rate law expression.
The i<em>ntegrated rate law for a first-order reaction </em>is
ln([A₀]/[A] ) = kt
Data:
[A]₀ = 750 mg
[A] = 68 mg
t_ ½ = 15 da
Step 1. Calculate the value of the rate constant.
t_½ = ln2/k Multiply each side by k
kt_½ = ln2 Divide each side by t_½
k = ln2/t_½
= ln2/15
= 0.0462 da⁻¹
Step 2. Calculate the time
ln(750/68) = 0.0462t
ln11.0 = 0.0462t
2.40 = 0.0462t Divide each side by 0.0462
t = 52 da
Aluminum is one of the main factors that reduce plant growth in acid soils. Although it is generally harmful to plants in soils with a neutral medium, the concentration of positive aluminum ions in acid soils increases and malfunctions in root and function growth.
Most acid soils are saturated with aluminum rather than hydrogen ions. Soil acidity is the result of hydrolysis of aluminum compounds. This principle (lime correction) to determine the degree of base saturation in the soil has become the basis of the methods used in soil testing laboratories to determine the lime requirements for soil. Application of lime to soil reduces the toxicity of aluminum to plants. Note This connector loads slowly.
Adaptation of wheat to allow aluminum to be carried out is due to the fact that aluminum releases organic compounds that in turn combine with harmful aluminum cations. It is believed that sorghum has the same endurance. The first genes found to withstand aluminum were found in wheat. Aluminum sulphide bearing has been found to be governed by an individual gene, such as in wheat. This is not the case in all plants.
