<span>Negatively charged R-groups in the primary structure.
This is because nickel acts as a cation, therefore you would be attracting anions, in this case it would be on the proteins that would be binding to the column. Once they bind to the matrix a was buffer of high salts can elute the proteins.</span>
To solve the problem, let us note that the calcium percentage no longer considers the moisture content of the canned dog food. Taking the 75% of the sample 681 grams results in a moisture content of 510.75. This is "removed" from consideration and we're left with 170.25 grams which we multiply with the given (dry basis) percentage of calcium to get 2.043 grams of Calcium.
it hydrostatic im not sure
