Question

Write balanced equations for each of the following by inserting the correct coefficients in the blanks:

1. ${\mathbf{\_SO}}_{\mathbf{2}}\left(g\right)\mathbf{+}{\mathbf{\_O}}_{\mathbf{2}}\left(g\right)\mathbf{\to }{\mathbf{\_SO}}_{\mathbf{3}}\left(g\right)$
   
2. ${\mathbf{\_Sc}}_{\mathbf{2}}{\mathbf{O}}_{\mathbf{3}}\left(s\right)\mathbf{+}{\mathbf{\_H}}_{\mathbf{2}}\mathbf{O}\left(l\right)\mathbf{\to }\mathbf{\_Sc}{\left(\mathrm{OH}\right)}_{\mathbf{3}}\left(s\right)$
   
3. ${\mathbf{\_H}}_{\mathbf{3}}{\mathbf{PO}}_{\mathbf{4}}\left(\mathrm{aq}\right)\mathbf{+}\mathbf{\_NaOH}\left(\mathrm{aq}\right)\mathbf{\to }{\mathbf{\_Na}}_{\mathbf{2}}{\mathbf{HPO}}_{\mathbf{4}}\left(\mathrm{aq}\right)\mathbf{+}{\mathbf{\_H}}_{\mathbf{2}}\mathbf{O}\left(l\right)$
   
4. ${\mathbf{\_C}}_{\mathbf{6}}{\mathbf{H}}_{\mathbf{10}}{\mathbf{O}}_{\mathbf{2}}\left(s\right)\mathbf{+}{\mathbf{\_O}}_{\mathbf{2}}\left(g\right)\mathbf{\to }{\mathbf{\_CO}}_{\mathbf{2}}\left(g\right)\mathbf{+}{\mathbf{\_H}}_{\mathbf{2}}\mathbf{O}\left(g\right)$
   

Short answer

1. $2{\mathrm{SO}}_2\left(\mathrm{g}\right)+{\mathrm{O}}_2\left(\mathrm{g}\right)\to 2{\mathrm{SO}}_3\left(\mathrm{g}\right)$
   
2. ${\mathrm{Sc}}_2{\mathrm{O}}_3\left(\mathrm{s}\right)+3{\mathrm{H}}_2\mathrm{O}\left(\mathrm{l}\right)\to 2\mathrm{Sc}{\left(\mathrm{OH}\right)}_3\left(\mathrm{s}\right)$
   
3. ${\mathrm{H}}_3{\mathrm{PO}}_4\left(\mathrm{aq}\right)+2\mathrm{NaOH}\left(\mathrm{aq}\right)\to {\mathrm{Na}}_2{\mathrm{HPO}}_4\left(\mathrm{aq}\right)+2{\mathrm{H}}_2\mathrm{O}\left(\mathrm{aq}\right)$
   
4. ${\mathrm{C}}_6{\mathrm{H}}_{10}{\mathrm{O}}_5\left(\mathrm{s}\right)+6{\mathrm{O}}_2\left(\mathrm{g}\right)\to 6{\mathrm{CO}}_2\left(\mathrm{g}\right)+5{\mathrm{H}}_2\mathrm{O}\left(\mathrm{g}\right)$
   

Step-by-step solution

Step1. Considering the following chemical equations:

Balancing all atoms other than H and O, after that balanced O and H Then checked overall equation is balanced or not.

For balancing the equation we chose firstly the most complicated looking molecule in the equation. For example C₆H₁₀O₅.

Step2. The final balanced reaction:

1. $2{\mathrm{SO}}_2\left(\mathrm{g}\right)+{\mathrm{O}}_2\left(\mathrm{g}\right)\to 2{\mathrm{SO}}_3\left(\mathrm{g}\right)$
   
2. ${\mathrm{Sc}}_2{\mathrm{O}}_3\left(\mathrm{s}\right)+3{\mathrm{H}}_2\mathrm{O}\left(\mathrm{l}\right)\to 2\mathrm{Sc}{\left(\mathrm{OH}\right)}_3\left(\mathrm{s}\right)$
   
3. ${\mathrm{H}}_3{\mathrm{PO}}_4\left(\mathrm{aq}\right)+2\mathrm{NaOH}\left(\mathrm{aq}\right)\to {\mathrm{Na}}_2{\mathrm{HPO}}_4\left(\mathrm{aq}\right)+2{\mathrm{H}}_2\mathrm{O}\left(\mathrm{l}\right)$
   
4. ${\mathrm{C}}_6{\mathrm{H}}_{10}{\mathrm{O}}_5\left(\mathrm{s}\right)+6{\mathrm{O}}_2\left(\mathrm{g}\right)\to 6{\mathrm{CO}}_2\left(\mathrm{g}\right)+5{\mathrm{H}}_2\mathrm{O}\left(\mathrm{g}\right)$