You have been supplied with a concentrated solution of calcium dihydrogen phosphate to be used in a hydroponic system to grow lettuce. The solution has a phosphorus concentration of 200 mg/ L, however, in a hydroponic nutrient solution, the common range of elemental phosphorus required is 30-50 mg/L. Explain how you would prepare a solution containing 35 mg/L phosphorus in a 500 mL volume?

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.

Is a pencil falling to the floor anon contact force, a force, or a contact force

An atom with 7 protons, 6 neutrons, and 7 electrons has an atomic mass of amu. (enter a whole number.) numerical answers expected! answer for blank 1: