If a motionless object has a weight of 25 n, what is true of the normal force acting on the object? a. it is 25 n and acts in the same direction as the weight. b. it is 25 n and acts in the opposite direction to the weight. c. it is less than 25 n and acts in the opposite direction to the weight. d. it is more than 25 n and acts in the opposite direction to the weight.

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.

What is the chemical equation of fire?

How many moles are in 4.6 x 10^19 atoms? *#27 is the question