Question

balance the equation: h₂so₄ + naoh --> na₂so₄ + h₂o. what is the coefficient on naoh? 3 1 2 4 question 2 1 pts balance the equaton: c₂h₆o + o₂ --> co₂ + h₂o what is the coefficient on o₂? 2 4 3

Explanation:

Step1: Balance the first equation

We have $H_2SO_4+NaOH
ightarrow Na_2SO_4 + H_2O$. First, balance the sodium ($Na$) atoms. There are 2 $Na$ atoms in $Na_2SO_4$, so we need 2 moles of $NaOH$. The balanced equation is $H_2SO_4 + 2NaOH=Na_2SO_4+2H_2O$.

Step2: Balance the second equation

For $C_2H_6O+O_2
ightarrow CO_2 + H_2O$, first balance the carbon atoms. There are 2 carbon atoms in $C_2H_6O$, so we put a 2 in front of $CO_2$: $C_2H_6O+O_2
ightarrow 2CO_2+H_2O$. Then balance the hydrogen atoms. There are 6 hydrogen atoms in $C_2H_6O$, so we put a 3 in front of $H_2O$: $C_2H_6O+O_2
ightarrow 2CO_2 + 3H_2O$. Now balance the oxygen atoms. On the right - hand side, we have $2\times2 + 3\times1=7$ oxygen atoms. In $C_2H_6O$, there is 1 oxygen atom. So we need 3 moles of $O_2$ to get 6 more oxygen atoms, and the balanced equation is $C_2H_6O+3O_2 = 2CO_2+3H_2O$.

Answer:

1. C. 2
2. C. 3