Radioactivity another name for radioactive decay. Radioactivity refers to particles emitted from nuclei as a result of nuclear instability.
That would be the compound Ba(NO3)2. The Barium ion has a charge of 2+ so there are 2 NO3- ions in the formula to produce a neutral compound.
<span>Kr has 8 valence electrons plus 1 for each Kr-F single bond. Total = 10 elcetrons
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1000 is the answer to the queshtion
The valence of helium is 0.
