How do you write the chemical equation (with state symbols) for the reaction? Which of the two reactants is the limiting reagent? How do you calculate the mass of carbon dioxide produced and the mass of the excess reactant left unreacted?

Question

5.00 g of solid copper (II) carbonate was allowed to react with 1.17 g of aqueous hydrochloric acid, to give aqueous copper (II) chloride, water and carbon dioxide gas.

Peyton Adams · Accepted Answer

The stoichiometric equation is:

#CuCO_3(s) + 2HCl(aq) rarr CuCl_2(aq) + H_2O(aq) + CO_2(g)uarr# I just learned that metal carbonates reacted with hydrochloric acids to form metal chloride, carbon dioxide, and water, which is how I was able to write this: #MCO_3(s) + 2HCl(aq) rarr MCl_2(aq) + CO_2(g)uarr + H_2O(l)# The fact that mass and charge are always balanced will help you learn these equations, though—are they balanced here? Are you sure? If we dig a little deeper, what we have labelled as #MCl_2(aq)# is probably the hexa-aqua complex, #[M(OH_2)_6]^(2+)# and #2xxCl^(-)(aq)#, but the given equation allows us to make stoichiometric predictions. #"Moles of copper carbonate"# #=# #(5.00*g)/(123.56*g*mol^-1)# #=# #0.0405*mol#. Now if the hydrochloric acid were prepared with #1.17*g# of hydrogen chloride gas (this is not what the question proposed; it could be #1.17*g# of conc. hydrochloric acid), there are #(1.17*g)/(36.46*g*mol^-1)# #=# #0.0321*mol#, and clearly, the hydrochloric acid is the limiting reagent. And thus only #0.0161*mol# of #CuCl_2(aq)# and #CO_2(g)# would be produced. In any case, I will let you elaborate on the query.

Cameron Andrews · Answer

undefined To write the chemical equation for the reaction, we need to know the specific reaction involved. Once we have the reaction, we can balance it and include state symbols to indicate the physical states of the reactants and products (e.g., (s) for solid, (l) for liquid, (g) for gas, and (aq) for aqueous solution).

To determine the limiting reagent, we compare the stoichiometry of the reactants to see which one would be consumed first based on their molar ratios.

To calculate the mass of carbon dioxide produced, we use stoichiometry and the mass of the limiting reagent consumed. We convert the mass of the limiting reagent to moles using its molar mass, then use the stoichiometric coefficients from the balanced equation to determine the moles of carbon dioxide produced. Finally, we convert moles of carbon dioxide to mass using its molar mass.

To calculate the mass of the excess reactant left unreacted, we subtract the mass of the limiting reagent consumed from the initial mass of the excess reactant. This gives us the mass of the excess reactant remaining after the reaction is complete.