<span>Boron has a lot of different isotopes, most of which having a very short half life (ranging from 770 milliseconds for Boron-8 down to 150 yoctoseconds for boron-7). But the two isotopes Boron-10 and Boron-11 are stable with about 80.1% of the naturally occurring boron being boron-11 and the remaining 19.9% being boron-10. The weighted average weight of those 2 isotopes has the value of 10.81.
The reason they use the average mass of an element for it's atomic weight is because elements in nature are rarely single isotopes. The weighted average allows us to easily compare relative number of atoms of one element against relative numbers of atoms of another element assuming that the experimenters are getting isotope ratios close to their natural ratios.</span>
Answer:
Wave particle duality is most apparent in analyzing the motion of. an electron. A photon of which electromagnetic radiation has the most energy.
Answer should be 20% so 1/5
In chemistry, there are two types of change, they are chemical and physical changes. A chemical change is one in which new substance are formed and it is always irreversible while a physical change is one in which no new substance is formed and it is always reversible. There are many factors that can indicate that a chemical change has taken place, these include: energy transfer, formation of precipitation, gas production, etc. Fracture formation does not indicate chemical change. In fracture formation nothing changes, so it is a form of physical change.
Your weight is a measure of ibs/pounds
