How many lead atoms are there in 0.250 moles of lead?

When the following equation is balanced using the smallest possible integers, what is the coefficent of oxygen gas? c7h16o(g) + o2(g) → co2(g) + h2o(g) -1 -5 -8 -16 -21

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 magnitude of the force of gravity between to 1000 kg cars which are separated by distance of 25. 0 km on an interstate highway? the force between the two cars will be what