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Electrolysis of 10.0 g of a binary metal chloride deposits 6.207 g of the pure metal. what is the metal?

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co2 is correct buddy
User SJR
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Answer:

Thorium

Step-by-step explanation:

Hello,

In this case, we have four options for the metals to be copper (63.5g/mol), cadmium (112.4g/mol), cerium (140g/mol) and thorium (232g/mol) in addition to the expected chemical reaction:


MCl_x-->M+(x)/(2) Cl_2

We must consider that 10.0 grams of the binary metal chloride yields 6.207 f of the pure metal, nonetheless, based on each metal's oxidation states we have seven options which are listed below:


CuCl, \ CuCl_2,\ CdCl, CeCl_2,\ CeCl_3, \ CeCl_3 \ and \ ThCl_4

Now, a suitable strategy is to compute the metal's by mass percent in each option and compare it with the actual metal's by mass percent inferred from the statement which is 62.07% (6.207/10.0*100%). For instance, for
CuCl, the by mass percent of copper is:


\% Cu=(n_(Cu)m_(Cu))/(M_(CuCl)) *100\%

Whereas
n_(Cu) accounts for the number of atoms of copper in such compound,
m_(Cu) accounts for the copper's atomic mass and
M_(CuCl) accounts for the copper (I) chloride's molar mass which is 70.9 g/mol, thus:


\% Cu=(1*63.5)/(70.9)*100\% \\\% Cu=89.6\%

Such value does not dovetail with the percent computed from the statement (62.07%), in this manner, after doing it for all the metals, the only one that matches is the
ThCl_4 as shown below:


\% Th=(1*232)/(373.8)*100\% \\\% Th=62.07\%

Therefore, the metal is thorium.

Best regards.

User Miguel Perher
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