Obviously the more product you have and the closer the impurities are, the more silica gel you will need. 1  A good rule of thumb is: 2  for difficult separations (Î´CV â¤ 1) use up to 100 g (~200 mL) of silica gel per gram of compound to be purified (1% load)
Median age at first marriage for American Indian and Alaska Native men and women age 15 to 54, respectively, in 2010. For the population as a whole in this age range, the respective numbers were 28.7 and 26.7 years. The difference in the median age at first marriage between American Indian and Alaska Native women and women overall is not statistically significant.
The average age in Congress has remained within a rather small range since World War II. The average age in the Senate was 59 in 1945, compared to 62 in 2011. The House has aged more substantially, with the average rising from 53 in 1945 to 57 in 2011. Between those years, average age fluctuated irregularly. Dips and surges in the age of our legislators probably have less to do with our attitudes toward the elderly than with views about incumbents.