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>
Answer:
Technology helps us in many ways.
Explanation:
We can now research the world even more effectively and at a higher level of sophistication thanks to technological advancements. Telescopes, on the other hand, enable us to peer into the far corners of the universe and detect very large objects such as stars. Electron microscope enable us to see smaller objects such as cells and organisms.
The number of grams of NaCl required to make 150.0 ml of a 5.000m solution is 43.875 grams
<u><em>calculation</em></u>
Step 1: calculate moles of NaCl
moles= molarity x volume in liters
volume in liters = 150.0 ml/1000= 0.15 l
moles is= 5.000mol/l x0.15 l =0.75 moles
Step2 : find mass
mass= moles x molar mass
molar mass of NaCl= 23 +35.5 = 58.5 g/mol
mass= 0.75 moles x58.5 g/mol = 43.875 grams
Answer:
Yes! It's because of like freezing and or solidification. It's the phase transition in which a liquid turns into a solid. It's when the temperature is lowered to or below a type of freezing point.
Explanation:
