Which of these can be classified as a pure substance?

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The image shows a process that releases nuclear energy which statement best identifies the process shown the process must be fusion because energy is released the process must be fusion because of have your nucleus formed a smaller nuclei the process must be fission because a large nucleus breaks into smaller nuclei the process must be fission because neutrons are formed

According to periodic trend, which of the following most likely has the highest ionization energy? kr be ni sc