Answer:
At earlier times elements were arrangrd on the basis of their atomic masses to study their properties easily but there were various problems like isotopes needs different position in perodic table.
After discovery of atomic number modern periodic table was created on the basis of atomic number (number of proton) that is unique for each element and varies regularly. So study of a group of elements is much easier than each element seperately that is why modern periodic table was formed.
Explanation:
Educated Guess Here!
Since Br-80 does not exist, maybe that means Br-79 or Br-81 have very unequal abundances. For example, Br-79 may have 75% abundance whereas Br-81 may have 25% abundance.
Answer:
Option A. 70.0 KPa.
Explanation:
Data obtained from the question include:
Pressure (torr) = 525.4 torr
Pressure (kPa) =?
The pressure expressed in torr can be converted kPa as shown below:
760 torr = 101.325 KPa
Therefore,
525.4 torr = (525.4 x 101.325) / 760 = 70.0 KPa.
Therefore, 525.4 torr is equivalent to 70.0 KPa.
I think it is 1620 (lxwxh) x 10 to get to millimeters
