ACROSS 1- light nuclei fuse together to form to a heavier nucleus 2- subatomic particle with a positive charge 3- isotope of hydrogen with 1 proton and 1 neutron 4- the lightest element 5- isotope of hydrogen with 1 proton and 2 neutrons 6- with a negative charge 7- symbol for lithium & symbol for helium DOWN 1- creates new atomic nucleus from preexisting nucleons 2- subatomic particle with a zero charge 3- symbol for beryllium 4- densely part of an atom containing p and n 5- ability to do work