This is a mass to mass stoichiometry conversion please help I need all work shown.

Imagine that you have produced several versions of lactase, each of which differs from normal lactase by a single amino acid. describe a test that could indirectly determine which of the versions significantly alters the three-dimensional shape of the lactase protein.

Cucl2 + 2nano3 cu(no3)2 + 2nacl what is the percent yield of nacl if 31.0 g of cucl2 reacts with excess nano3 to produce 21.2 g of nacl? 49.7% 58.4% 63.6% 78.7%

Which of the following represents a balanced nuclear equation showing bismuth-212 undergoing alpha decay followed by beta decay? (2 points) superscript 212 over subscript 83 bi yields superscript 4 over subscript 2 he + superscript 208 over subscript 81 tl yields x−superscript 208 over subscript 82 pb + superscript 0 over subscript -1 beta superscript 212 over subscript 83 bi + superscript 0 over subscript -1 beta yields superscript 4 over subscript 2 he + superscript 208 over subscript 81 tl yields x−superscript 208 over subscript 82 pb superscript 216 over subscript 85 as yields superscript 4 over subscript 2 he + superscript 216 over subscript 85 as yields superscript 216 over subscript 85 pb + superscript 0 over subscript -1 beta superscript 212 over subscript 83 bi yields superscript 0 over subscript -1 beta + superscript 208 over subscript 81 tl yields superscript 208 over subscript 82 pb + superscript 4 over subscript 2 he