The partial pressure of 0.50 Ne gas is 214.71 torr
calculation
the partial pressure of Ne = moles of Ne/total moles x final pressure
find the total moles of the air mixture
that is moles of Ne + moles of K= 0.50 + 1.20 = 1.70 moles
The partial pressure is therefore = 0.50 /1.70 x 730 = 214.71 torr
I think it is the third statement
‘A unit is made up of two or more atoms’
Fluorine 20 (F - Atomic number 9 and atomic mass 20). Firstly we need to know what is beta decay. Beta decay occurs when one neutron changes into a proton and an electron therefore the atomic mass will remain the same as even though we loose a neutron it is replaced by a proton, the atomic number is always raised by 1 when one beta decay occurs. The produced electron is shot out of the nucleus at an incredible speed. This speedy electron we call a beta particle.
Ok now the reaction.
20 20 0
F -> Ne + e
9 10 -1
Remember the atomic number determines the nature of the element ( i.e what elemnt it is).
Hope this helps :).
Its period 5 from 5s25p6, with Xenon(54) as the noble gas. 2+6 = 8 electrons
54+8 = 62, or Sm.