Answer:

Explanation:
Given that:
Half life = 30 min
Where, k is rate constant
So,
The rate constant, k = 0.0231 min⁻¹
Using integrated rate law for first order kinetics as:
Where,
is the concentration at time t
is the initial concentration
Given that:
The rate constant, k = 0.0231 min⁻¹
Initial concentration
= 7.50 mg
Final concentration
= 0.25 mg
Time = ?
Applying in the above equation, we get that:-

Answer:
B, D, C
Explanation:
the solution may have more than one solute, a solution is a homogenous mixture of 2 or more substances and not all solutions are liquid
<span>If a reaction is reversible, then it will attain the phase of Equilibrium and at that phase, the Amount of Reactants and Products would be: Equal
Hope this helps!</span>
Answer:
A. (CH3)3C-I reacts by SN1 mechanism whose rate is independent of nucleophile reactivity.
Explanation:
We must recall that (CH3)3C-I is a tertiary alkyl halide. Tertiary alkyl halides preferentially undergo substitution reaction via SN1 mechanism.
In SN1 mechanism, the rate of reaction depends solely on the concentration of the alkyl halide (unimolecular mechanism) and is independent of the concentration of the nucleophile. As a result of this, both Br^- and Cl^- react at the same rate.
Answer:
This problem is providing a chemical equation between two hypothetical elements, X and Y and asks for the molesof X that are needed to
produce 21.00 moles of D in excess Y. After the following work, the answer turns out to be 15.75 mol X:Mole ratios:In chemistry, one the most crucial branches is stoichiometry, which allows us to perform calculations with grams, moles and particles (atoms, molecules and ions). It is based on the concept of mole ratios, whereby the moles of a specific substance can be converted to moles of another one, say product to reactant, reactant to reactant, reactant to product and product to product.
Calculations:In such a way, since 21.00 moles of D are given, we need the mole ratio of D to X in order to get the answer, which according to the reaction is 3:4 based on their coefficients in the reaction. Hence, we calculate the required as follows:
Explanation:
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