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: Hmmmm. Let's see...
Explanation: A pebble has the same density and a boulder when it rolls down a hill. The pebble will most-likely roll down very fast which can make it dense.
<h2 /><h2>I really hope this helped! like at all...</h2><h2>Truthfully, I don't know a lot of this type of stuff.. But worth a shot, right?</h2>
Answer:
Option A. (Be)
Explanation:
Beryllium is used in alloys with copper or nickel to make gyroscopes, springs, electrical contacts, spot-welding electrodes and non-sparking tools.
<h2>Answer:</h2><h2><em>Cellular respiration takes a glucose molecule and combines it with oxygen; the result is energy in the form of ATP, along with carbon dioxide and water as waste products. Photosynthesis takes carbon dioxide and combines it with water, enabled by radiant energy, usually from the sun.</em></h2><h2><em>Explanation:</em></h2><h2><em></em></h2>
