Which of the following isotopes has the same number of neutrons as phosphorus – 21 (atomic number 15)
a. 32/15 p
b. 32/16 s
c. 29/14 si
d. 28/14 si?

Why do you suppose the structural polysaccharide cellulose does not contain branches? why do you suppose the structural polysaccharide cellulose does not contain branches? branches in the molecule would generate side chains that would almost certainly make it difficult to pack the cellulose molecules into globules, thereby decreasing the flexibility and strength of the globules. branches in the molecule would generate side chains that would almost certainly make it difficult to pack the cellulose molecules into microfibrils, thereby increasing the rigidity and strength of the microfibrils. branches in the molecule would generate side chains that would almost certainly make it difficult to pack the cellulose molecules into globules, thereby increasing the flexibility and strength of the globules. branches in the molecule would generate side chains that would almost certainly make it difficult to pack the cellulose molecules into microfibrils, thereby decreasing the rigidity and strength of the microfibrils.

11. phosphorus-32 is radioactive and has a half life of 14 days. how much of a 124 mg sample of phosphorus-32 is present after 56 days? a) 7.75 mg b) 15.5 mg c) 31.0 mg d) 62.0 mg

In 2002, the rare earth elements mine in mountain pass, california was closed because