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irina [24]
3 years ago
13

naturally occurring bromine molecules, br2 have masses of 158, 160, and 162. they occur in the relative abundances 25.69%, 49.99

%, and 24.31% respectively. what is the average atomic mass of bromine atoms? what is the relative abundance of 79br and 81br isotopes?
Chemistry
1 answer:
4vir4ik [10]3 years ago
4 0
The average atomic mass of an element can be determined by multiplying the individual masses of the isotopes with their respective relative abundances, and adding them. 

Average atomic mass of Br = 158 amu(0.2569) + 160 amu(0.4999) + 162 amu(0.2431)
Average atomic mass = 159.96 amu

As described in the problem, the relative abundance for Br-79 is 25.69%. This is because 2 atoms of Br is equal to 79*2 = 158 amu. Similarly, the relative abundance of Br-81 is 81*2 = 162, which is 24.31%.
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C. Carbon dioxide

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The burning fossil fuels for electricity, industry, heat, and transportation are the major sources of the emossion of carbon dioxide.

Also, the cutting down of trees for paper production, building construction and for the establishment of settlements also increase the concentration of carbon dioxide in the atmosphere. Trees are help remove carbon dioxide from the atmosphere through the process of photosynthesis. However, when these trees are cut down, carbon dioxide accumulates in the atmosphere.

5 0
3 years ago
Select all that apply to physical and chemical properties ?
MaRussiya [10]

Answer:

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7 0
3 years ago
Read 2 more answers
What is the density (g/mL) of an object that has a mass of 0.03 kg and occupies a volume of 25 mL?
tatyana61 [14]
First convert the kg to g ----- 0.03kg = 30g
Then divide the mass by the volume ----- 30g ÷ 25mL = 1.2
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5 0
3 years ago
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I WILL GIVE BRAINLIEST TO BEST AND MOST THOROUGH ANSWER!
andrew11 [14]
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7 0
3 years ago
How many orbitals surround the nucleus in a neutral atom of sulfur (S)?
Leto [7]
<h2>C</h2>

Explanation:

The atomic number of S is 16

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So,the number of orbitals involved is 9.

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3 years ago
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