The average atomic mass of the imaginary element : 47.255 amu
<h3>Further explanation </h3>The elements in nature have several types of isotopes
Isotopes are elements that have the same Atomic Number (Proton)
Atomic mass is the average atomic mass of all its isotopes
Mass atom X = mass isotope 1 . % + mass isotope 2.% ..
isotope E-47 47.011 amu, 87.34%
isotope E-48 48.008 amu, 6.895
isotope E-49 50.009 amu, 5.77%
The average atomic mass :
Answer:
The number of moles of KClO₃ reacted was 0,15 mol
Explanation:
For the reaction:
2KClO₃(s) → 2KCl(s) + 2O₂(g)
The only gas product is O₂.
Total pressure is the sum of vapor pressure of water with O₂ gas formed. Thus, pressure of O₂ is:
749mmHg - 23,8mmHg = 725,2mmHg
Using gas law:
PV/RT = n
Where:
P is pressure (725,2mmHg ≡ <em>0,9542atm</em>)
V is volume (<em>5,76L</em>)
R is gas constant (<em>0,082 atmL/molK</em>)
And T is temperature (25°C ≡ <em>298,15K</em>)
Replacing, number of moles of O₂ are <em>0,2248 moles</em>
As 2 moles of KClO₃ react with 3 moles of O₂ the moles of KClO₃ that reacted was:
0,2248 mol O₂× = <em>0,15 mol of KClO₃</em>
I hope it helps!