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%.
Answer: The reactivity of group 7 decreases as we move down the group because:
Explanation:
The elements of group 7 that is fluorine to iodine. The halogens are non metals and they react with metals to gain electrons. The metals loose electrons and the non metal gains it.
As we move down the group the atomic radius gets bigger( more electron and more proton) and as a result the outer shells move further away from the nucleus.
There is more distance between the negatively charged electrons and positively charged nucleus.
Therefore the force of attraction between the shells and nucleus is lesser or weaker.
This makes attracting an extra electron from metals very difficult which results in weaker reaction.
Consequently, the reactivity decreases as we move down the group 7
Answer:
During photosynthesis, plants absorb carbon dioxide and sunlight to create fuel—glucose and other sugars—for building plant structures. This process forms the foundation of the fast (biological) carbon cycle.
The Slow Carbon Cycle. ... Atmospheric carbon combines with water to form a weak acid—carbonic acid—that falls to the surface in rain. The acid dissolves rocks—a process called chemical weathering—and releases calcium, magnesium, potassium, or sodium ions.
Ok buddy sorry buddy I just got
Obsidian - extrusive igneous
granite - clastic sedimentary
conglomerate - intrusive igneous
evaporite - chemical sedimentary
coal - organic sedimentary
marble - metamorphic