The chemical reaction between mercuric chloride and potasisum oxalate proceeds as under:
`2HgCl_(2) + K_(2)C_(2)O_(4) rarr KCl + 2CO_(2) + Hg_(2)Cl_(2)`
The mass of `Hg_(2)Cl_(2)` precipitated form different solutions in a given time at `100^(@)C` was as follows:
`|{:("Experiment number",HgCl_(2) (mol L^(-1)),K_(2)C_(2)O_(4) (mol L^(-1)),"Time (min)",Hg_(2)Cl_(2) "precipitated (mole)"),(1,0.0836,0.404,65,0.0068),(2,0.0836,0.202,120,0.0031),(3,0.0418,0.404,60,0.0032):}|`
form the data calculate order of the reaction.

Explanation

Since mass `prop` moles `prop M`.
`:.` Rate `= k[HgCl_(2)]^(alpha)[K_(2)C_(2)O_(4)]^(beta)`
`(0.0068)/(65) = k[0.836]^(alpha)[0.404]^(beta)` …(i)
`(0.0031)/(120) = k[0.0836]^(alpha)[0.202]^(beta]` …(ii)
`(0.0032)/(60) = k[0.0418]^(alpha)[0.404]^(beta)` ...(iii)
Dividing Eq. (i) by (ii), we get `4 = 2^(beta) rArr beta = 2`
Dividing Eq. (i) by (iii), we get `2 = 2^(alpha) rArr alpha = 1`
Thus, overall order `alpha+beta = 3`