A reaction was experimentally determined to follow the rate law, Rate = k[A] where k = 0.15 s-1. Starting with [A]o = 0.225M, how many seconds will it take for [A]t = 0.0350M?

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the density of gold = 19.3 g/cm3

the relation between density and mass and volume is

density = mass / volume

given :

mass of gold = 13 g

density = 13g / volume = 19.3

volume = 13 /19.3 = 0.67 cm^3

thus volume of gold nugget = 0.67 cm^3