There are two stable isotopes of bromine . their masses are 78.9183 amu and 80.9163 amu. if the average atomic mass of bromine is 79.90 amu, what is the natural abundance of the lighter isotope?

Y=‐1x + 7 if y has a value of ‐24 what is the value of x?

1. suppose a reaction mixture, when diluted with water, afforded 300 ml of an aqueous solution of 30 g of the reaction product malononitrile [ch2(cn)2], which is to be isolated by extraction with ether. the solubility of malononitrile in ether at room temperature is 20.0 g/100 ml, and in water is 13.3 g/100 ml. what weight of malononitrile would be recovered by extraction with (a) three 100-ml portions of ether and (b) one 300-ml portion of ether? suggestion: for each extraction, let x equal the weight extracted into the ether layer. in part (a), the concentration in the ether layer is x/100 and in the water layer is (30 x)/300; the ratio of these quantities is equal to k 20/13.3.

When the speed of the bottle is 2 m/s, the average maximum height of the beanbag is m.