Answer:
The answer to your question is 203.8 g
Explanation:
Data
Average atomic mass = ?
Centium-200
Centium-203
Centium-209
Equal amounts
Process
1.- Determine the abundance of each isotope.
If they are in equal amounts in nature, just divide 100 by 3
100/3 = 33.33 % or 0.333
2.- Determine the Average atomic mass
Average atomic mass = Atomic mass 1 x abundance + Atomic mass 2 x
abundance + Atomic mass 3 x abundance
- Substitution
Average atomic mass = 200 x 0.333 + 203 x 0.333 + 209 x 0.333
- Simplification
Average atomic mass = 66.6 + 67.6 + 69.6
Result
Average atomic mass = 203.8 g
The percentage yield is 72.8 %.
<em>Step 1</em>. Calculate the <em>mass of Br₂</em>
Mass of Br₂ = 20.0 mL Br₂ × (3.10 g Br₂/1 mL Br₂) = 62.00 g Br₂
<em>Step 2</em>. Calculate the <em>theoretical yield</em>
M_r: 159.81 266.69
2Al + 3Br₂ → 2AlBr₃
Moles of Br₂ = 62.00 g Br₂ × (1 mol Br₂/(159.81 g Br₂) = 0.3880 mol Br₂
Moles of AlBr₃ = 0.3880 mol Br₂ × (2 mol AlBr₃/(3 mol Br₂) = 0.2586 mol AlBr₃
Theor. yield of AlBr₃ = 0.2586 mol AlBr₃ × 266.99 g AlBr₃)/(1 mol AlBr₃)
= 69.05 g AlCl₃
<em>Step 3</em>. Calculate the <em>percentage yield
</em>
% yield = (actual yield/theoretical yield) × 100 % = (50.3 g/69.05 g) × 100 %
= 72.8 %
A plasma is an ionized gas, a gas into which sufficient energy is provided to free electrons from atoms or molecules and to allow both species, ions and electrons, to coexist
Complete Question
You are given a solution containing a pair of enantiomers (A and B). Careful measurements show that the solution contains 98% A and 2% B. What is the enantiomeric excess?
Answer:
The value is 
Explanation:
From the question we are told that
The percentage of enantiomer A is A = 98%
The percentage of enantiomer B is B = 2%
Generally the enantiomeric excess is mathematically represented as
=> 
=>
