Matter is made up of protons, electrons, and neutrons. Protons and <1> are found in the nucleus. There are 92 naturally occurring substances with a unique number of protons in the nucleus known as <2>. The substance $mass$charge$sym has <3> protons, <4>electrons, and <5> neutrons. The electrons are held in orbit around the nucleus by the <6> force.
Electrons cannot orbit the nucleus at any distance. Instead there are only certain allowed distances from the nucleus that orbits can have which correspond to certain permitted energy levels. Electrons can jump to higher levels when the atom absorbs a photon or <7> another atom. The electron will eventually jump back to the lower level emitting the photon in a random direction.
There is considerable vocabulary related to transitions involving the hydrogen atom. Electron transitions involving the first level are known as <8> transitions while those involving the $level level are known as <9> transitions. When an electron in a hydrogen atom jumps from the $level2 level to the second it emits a <10> photon.
@ qu.1.1.algorithm= $num=rint(6); $sym=switch($num,"Fe","Cu","W","Zn","K","Fe","Cu"); $mass=switch($num,56,65,182,68,41,58,63); $charge=switch($num,26,29,74,30,19,26,29); $neutrons=switch($num,30,36,108,38,22,32,34); $num2=rint(2); $level=switch($num2,"second","third"); $trans=switch($num2,"Balmer","Paschen"); $wrongtrans=switch($num2,"Paschen","Balmer"); $num3=rint(3); $level2=switch($num3,"third","fourth","fifth"); $color=switch($num3,"red","blue/green","purple"); $badcolor1=switch($num3,"blue/green","purple","red"); $badcolor2=switch($num3,"purple","red","blue/green"); @ qu.1.1.blank.1=neutrons, electrons, molecules, ions@ qu.1.1.blank.2=elements, atoms, molecules, ions@ qu.1.1.blank.3=$charge,22,30,32,34,36,38,108@ qu.1.1.blank.4=$charge,22,30,32,34,36,38,108@ qu.1.1.blank.5=$neutrons,19,26,29,30,33,54,74@ qu.1.1.blank.6=electromagnetic, strong nuclear, weak nuclear, gravitational@ qu.1.1.blank.7=collides with, takes the energy of, releases a photon to, absorbs electrons from@ qu.1.1.blank.8=Lyman, Balmer, Paschen, Brackett@ qu.1.1.blank.9=$trans,$wrongtrans, Lyman, Brackett@ qu.1.1.blank.10=$color,$badcolor1,$badcolor2,yellow@ qu.1.1.grader.1=menu@ qu.1.1.grader.2=menu@ qu.1.1.grader.3=menu@ qu.1.1.grader.4=menu@ qu.1.1.grader.5=menu@ qu.1.1.grader.6=menu@ qu.1.1.grader.7=menu@ qu.1.1.grader.8=menu@ qu.1.1.grader.9=menu@ qu.1.1.grader.10=menu@