You have been working to develop a new fictitious compound in the lab. Determine the amount in units of moles [mol] of 20 grams
[g] of this compound. The compound has the formula: upper x 2 upper y 2 upper z 7, where the components are x, amu equals 47; y, amuequals42; z, amu equals 16.
From the chemical formula the total mass of the compound can be determined. The mass of the 1 mole of the compound is its molar mass. The atom by which the molecule is generated, the mass of these atoms are expressed in terms of amu or atomic unit mass, but after formation of a molecule in a particular ratio the mass of each of the atom becomes the total molecular weight of the generated molecule. In this case the molecule posses three atoms X, Y and Z which are in a ratio of 2:2:7. Thus the chemical formula of the compound can be written as .
So the total mass of the compound in amu is {(2×47)+(2×42)+(7×16)} = {94+84+112}=290 amu.
Thus 1 mole of the compound contains 290 amu or 290 g by mass.
Henceforth 20 gram of the compound is equivalent to (20/290) = 0.068 mole.
The advantage of this technique is that purified water as well as deposited metals can be re-used. It is necessary to use an inert electrode, such as platinum, because there is no metal present to conduct the electrons from the anode to the cathode.
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Soda is carbonated water. It contains carbon dioxide dissolved in water , which is carbonic acid. On opening the soda, the carbonic acid undergoes the reverse reaction and releases carbon dioxide in the air . The soda is thus left with just water and loses it's fizz.
