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:
when lit, the atoms of different chemical compounds inside the firework absorb energy, when the electrons fall back to lower energy levels, they give off colored light. Depending upon the chemical used, different colors are produced. neon lights or signs are glass tubes filled with neon gas. When the light is plugged in, the electrical energy causes the electrons of neon to jump to higher energy levels, when they go to lower levels, colored light is given off. The neat thing is that the neon never gets used up. The only thing that gets used up is the electricity. The electrons don't get destroyed and can be used over and over again jumping levels. Neon glows with an orange light, but you know that neon signs can be lots of different colors. The variations come when different gases other than neon are used such as argon, or krypton or when the tube is painted so that with the light produced it produces a certain color.
Explanation:
Answer:
I think it is E part electron's are lost
Answer:
100
Explanation:
Step 1: Subtract 50 by 300 to find the total mass of the marbles
300 - 50 = 250
Not hard, right?
Step 2: Divide 250 by 2.5
250 ÷ 2.5 = 100
And... 100 is your answer :)
Hope this helps :)
-jp524
6 protons, 7 neutrons, and if it has no charge then it has 6 electrons
