Atomic mass of Br = 79.904
<span>Now lets say y% is abundance of 79Br. </span>
<span>Then abundance of 81Br = (100 - y) </span>
<span>mass due to 79Br = 78.9183 * y/100 = 0.789183y
</span><span>mass due to 81Br = 80.9163 x (100 - y)/100 = 0.809163(100 - y) </span>
<span>Therfore</span>
<span>0.789183y+ 0.809163(100 - y) = 79.904 </span>
<span>0.789183y + 80.9163 - 0.809163y = 79.904 </span>
<span> - 0.01998y= 79.904 - 80.9163
= - 1.0123 </span>
<span>y = 1.0123/0.01998 = 50.67% </span>
<span> 79Br = 50.67% </span>
<span>now
81Br = 100 - 50.67 = 49.33%
hope this helps</span>
The answer is 341.7 g.
(1) Calculate the molar mass (M) of CaCl2 which is the sum of atomic masses (A) of elements:
M(CaCl2) = A(Ca) + 2A(Cl)
A(Ca) = 40.1 g/mol
A(Cl) = 35.45 g/mol
M(CaCl2) = 40.1 + 2 * 35.45 = 40.1 + 70.9 = 111 g/mol
(2) Calculate in how many moles are 535 g:
M(CaCl2) = 111 g/mol
111g : 1mol = 535 g : xmol
x = 535 g * 1mol : 111g = 4.82 mol
(3) Calculate how many grams of Cl are in 4.82 mol:
A(Cl) = 35.45 g/mol
2A(Cl) = 2 * 35.45 = 70.9 g/mol
70.9 g : 1 mol = x : 4.82 mol
x = 70.9 g * 4.82 mol : 1 mol = 341.7 g
Answer:
There are 8Si atoms and 16 O atoms per unit cell
Explanation:
From the question we are told that:
Edge length 
Density 
Generally the equation for Volume is mathematically given by
Where
Molar mass of (SiO2) for one formula unit
Therefore
Density of Si per unit length is
Molar mass of (SiO2) for one formula unit
Therefore
There are 8Si atoms and 16 O atoms per unit cell
The step in the water cycle when this happens is Condensation
