pH scale is used to determine the acidity of a solution
pH is calculated using the H⁺ concentration
pOH scale is used to determine how basic a solution is
pOH is calculated using the OH⁻ concentration
pH and pOH are related in the following formula
pH + pOH = 14
pH = 3
pOH = 14 - 3
pOH = 11
pOH is calculated using the following formula
pOH = - log[OH⁻]
[OH⁻] = antilog(-pOH)
[OH⁻] = antilog(-11)
[OH⁻] = 1 x 10⁻¹¹ M
the [OH⁻] concentration of lemon juince is D) 1 x 10⁻¹¹ M
Balanced equation :
3H₂+N₂⇒2NH₃
<h3>Further explanation</h3>
Equalization of chemical reaction equations can be done using variables. Steps in equalizing the reaction equation:
1. gives a coefficient on substances involved in the equation of reaction such as a, b, or c etc.
2. make an equation based on the similarity of the number of atoms where the number of atoms = coefficient × index between reactant and product
3. Select the coefficient of the substance with the most complex chemical formula equal to 1
Unbalanced⇒the number of atoms from both sides (reactants and products) is not the same
H₂+N₂⇒NH₃
H=2(left), H=3(right)
N=2(left), N=1(right)
Balanced ⇒ the number of atoms from both sides (reactants and products) is equal
3H₂+N₂⇒2NH₃
H=3x2=6(left), H=2x3=6(right)
N=2(left), N=2x1=2(right)
4C₃H₅(NO₃)₃
------> 12CO₂
+ 6N₂
+ 10H₂O
+ O₂
mol of CO₂ = 
= 
mol ratio of CO₂ : C₃H₅(NO₃)₃
12 : 4
∴ if mole of CO₂ = 0.568 mol
then " " C₃H₅(NO₃)₃ = 
= 0.189 mol
∴ mass of nitroglycerin = mole * Mr
= 0.189 mol * 227.0995 g / mol
= 43.00 g
They are not always identical because they have different isotope numbers which develops different neutrons numbers