Answer:
% = 76.75%
Explanation:
To solve this problem, we just need to use the expressions of half life and it's relation with the concentration or mass of a compound. That expression is the following:
A = A₀ e^(-kt) (1)
Where:
A and A₀: concentrations or mass of the compounds, (final and initial)
k: constant decay of the compound
t: given time
Now to get the value of k, we should use the following expression:
k = ln2 / t₁/₂ (2)
You should note that this expression is valid when the reaction is of order 1 or first order. In this kind of exercises, we can assume it's a first order because we are not using the isotope for a reaction.
Now, let's calculate k:
k = ln2 / 956.3
k = 7.25x10⁻⁴ d⁻¹
With this value, we just replace it in (1) to get the final mass of the isotope. The given time is 1 year or 365 days so:
A = 250 e^(-7.25x10⁻⁴ * 365)
A = 250 e^(-0.7675)
A = 191.87 g
However, the question is the percentage left after 1 year so:
% = (191.87 / 250) * 100
<h2>
% = 76.75%</h2><h2>
And this is the % of isotope after 1 year</h2>
Answer= Maximum amount of product that could be obtained under ideal conditions from a given amount of reactants.
Explanation:
The theoretical yields is the ideal maximum amount of a product that can be produced during a chemical reaction while the limiting reactant is the reactant that determines the maximum amount of product that can be formed. mitgliedd1 and 61 more users found this answer helpful.
Answer:
Explanation:
They gave us the masses of two reactants and asked us to determine the mass of the product.
This looks like a limiting reactant problem.
1. Assemble the information
We will need a chemical equation with masses and molar masses, so, let's gather all the information in one place.
Mᵣ: 239.27 32.00 207.2
2PbS + 3O₂ ⟶ 2Pb + 2SO₃
m/g: 2.54 1.88
2. Calculate the moles of each reactant
3. Calculate the moles of Pb from each reactant
4. Calculate the mass of Pb
Answer:
<em>It is known by almost everyone Earth is divided into longitudes and latitudes which are imaginary lines that cut Earth into 2 equal parts.</em>
Explanation:
The main use of dividing Earth into so many imaginary lines is to know no of places perfect location in numbers. Direction and tell tales can make the place talked about a bit confusing but the exact longitudes and latitudes known pill and someone in exact position.
So in the positions given the question 27 ° and 19 ° show the distance of longitude from Prime Meridian While 18 ° and two degrees show the distance from the equator.
