What mass of oxygen gas contains the same
number of moles as 56g of sulphur?
(Relative atomic mass: S=32,0=16)
(A) 0.56 g
B) 5.6 g
(C) 56 g
C) 560g

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.

How many moles is 14.5 cm^3 of platinum? the density of platinum is 21.45 g/cm^3.

Amixture initially contains a, b, and c in the following concentrations: [a] = 0.300 m , [b] = 1.05 m , and [c] = 0.550 m . the following reaction occurs and equilibrium is established: a+2b⇌c at equilibrium, [a] = 0.140 m and [c] = 0.710 m . calculate the value of the equilibrium constant, kc.