If 13.3 moles of Cu and 43.2 moles of HNO3 are allowed to react, how many moles of excess reactant will remain if the reaction goes to completion? 3 Cu + 8 HNO3 → 3Cu(NO3)2 + 2NO + 4H2O
1 Answer
Explanation:
Write the balanced equation and the given data.
#(color(red)(3)Cu)/color(red)(13.3mol)+(color(blue)8HNO_3)/color(blue)(43.2mol)->3Cu(NO_3)_2+2NO+4H_2O#
Determine how many moles each reactant needed if the reaction goes into completion. Refer to the balanced equation for the mole ratios; i.e.,
#ul(etaCu=13.3mol)#
#=13.3cancel(molCu)xx(color(blue)(8)molHNO_3)/(color(red)(3)cancel(molCu))#
#=35.5molHNO_3#
#:.#
#color(red)(13.3molCu)-=color(blue)(35.5molHNO_3)#
#color(blue)((etaHNO_3 " available")/(43.2mol)>(etaHNO_3" required")/(35.5mol))#
#ul(etaHNO_3=43.2mol)#
#=43.2cancel(molHNO_3)xx(color(red)(3)molCu)/(color(blue)(8)cancel(molHNO_3))#
#=16.2molCu#
#:.#
#color(blue)(43.2molHNO_3)-=color(red)(16.2molCu)#
#color(red)((etaCu " available")/(13.3mol)<(etaCu" required")/(16.2mol)#
Therefore, the
#eta " x's reactant "=etaHNO_3" available."-etaHNO_3" req'd"#
#eta " x's reactant "=43.2molHNO_3-35.5molHNO_2#
#eta " x's reactant "=7.7molHNO_3#