The first elements to be produced in the laboratory were plutonium and neptunium. Neptunium was produced by bombarding Uranium-238 with neutrons, which led to the
formation of beta particles and neptunium. Which of the following is the most accurate
description of the process?
F. O
238 1
U +
92 0
n-
0 239
e +
Np
-1 93
G
238 1
U + n-
92 0
0 239
e + Np
-1 94
Н.
238 0 1 237
U + e- - n +
Np
92 -1 0 93
1
J. O
238
92
238
U + = n =
0 93
Np +

the ozone layer acts as a filter for the shorter wavelength and highly hazardous ultraviolet radiation (uvr) from the sun, protecting life on earth from its potentially harmful effects. when the sky is clear, there is an inverse relationship between stratospheric ozone and solar uvr measured at the earth's surface.

  the   balanced   equation   for   reaction of   ca metal   with   o2 to   produce   cao   is as below

2 ca+ o2→ 2 cao2

  explanation

the reaction is   balanced     since the   number of atoms   in reactant side is   equal to   number of atoms   in   product side.   for   example   they   are 2   atom of   ca in   reactant   side   and   2   atoms of ca   in   the product side.

  the   process   is a   meet the   requirement   of   redox   reaction because :     calcium   is   oxidized   from   oxidation state 0   to 2+   while   oxygen   is reduced from   oxidation   state   0   to 2-

the answer is na (sodium)

un recipient conține 6,4 moli de gaz. gazul hidrogen reprezintă 25% din totalul kilometrilor din container. în cazul în care presiunea totală este de 1.24 atm ceea ce este