Cobalt-60 decays into nickel-60 via beta decay with a half-life of 5.27 years. A purse sample of cobalt-60 is prepared, with no contamination of other isotopes. After 5.27 years, what is the ratio of cobalt-60 to nickel-60 in the sample?

What amount of heat is exchanged when 106.2 grams of substance y goes from a liquid at 35 degrees celsius to a solid at the same temperature? melting point of substance y = 35 degrees c; δhvaporization = 3.67 j/mol; δhfusion = 3.30 j/mol. mwsubstance y = 28.22 g/mol. −12.4 j −3.51 x 102 j 1.24 x 101 j 351 j