How many moles of Pb(NO3)2 are required
if 8 moles of AICI: are consumed?
3Pb(NO3)2 + 2AlCl3 + 3PbCl2 + 2A1(NO3)3

12 moles Pb(NO₄)₂ needed.

Explanation:

                3Pb(NO₃)₂ +2AlCl₃     => 3PbCl₂ + 2Al(NO₃)₃

Given =>   ? moles      8 moles

from reaction stoichiometry, 2 moles AlCl₃ requires 3 moles Pb(NO₄)₂ then 8 moles AlCl₃ requires 3/2(8) moles of the Pb(NO₄)₂ => 12 moles Pb(NO₄)₂ needed.

i just calculated it all out, and not including weekends, and all the different days off. as of this school year (2018-2019) students are spending 2198 hours in school this year

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the accuracy of the data.