Question

quentin titrates nitric acid with calcium hydroxide. balance the equation. what is the coefficient for nitric acid in balanced molecular equation? ?hno₃ + ca(oh)₂ → h₂o(l) + __ca(no₃)₂

Explanation:

Step1: Balance nitrate ions

On the right side, $\ce{Ca(NO_{3})_{2}}$ has 2 nitrate ($\ce{NO_3^-}$) ions. So, we put a coefficient of 2 in front of $\ce{HNO_3}$ to balance nitrate ions:
$2\ce{HNO_{3}} + \ce{Ca(OH)_{2}}
ightarrow \ce{H_{2}O} + \ce{Ca(NO_{3})_{2}}$

Step2: Balance hydrogen and oxygen (from hydroxide)

Now, left side has 2 $\ce{H^+}$ from $\ce{HNO_3}$ and 2 $\ce{OH^-}$ from $\ce{Ca(OH)_2}$, which form 2 $\ce{H_2O}$ (since $\ce{H^+ + OH^- -> H_2O}$). So, put a coefficient of 2 in front of $\ce{H_2O}$:
$2\ce{HNO_{3}} + \ce{Ca(OH)_{2}}
ightarrow 2\ce{H_{2}O} + \ce{Ca(NO_{3})_{2}}$

Step3: Check all elements

• $\ce{Ca}$: 1 on left, 1 on right (balanced).
• $\ce{N}$: 2 on left (from $2\ce{HNO_3}$), 2 on right (from $\ce{Ca(NO_3)_2}$) (balanced).
• $\ce{H}$: $2\times1 + 2\times1 = 4$ on left; $2\times2 = 4$ on right (balanced).
• $\ce{O}$: $2\times3 + 2\times1 = 8$ on left; $2\times1 + 2\times6 = 14$? Wait, no—wait, $\ce{HNO_3}$: 3 O per molecule, 2 molecules: 6 O. $\ce{Ca(OH)_2}$: 2 O. Total left O: 6 + 2 = 8. $\ce{H_2O}$: 1 O per molecule, 2 molecules: 2 O. $\ce{Ca(NO_3)_2}$: 6 O. Total right O: 2 + 6 = 8 (balanced).

All elements are balanced.

Answer:

2