I would say that what conserving mass in a chemical equation means is that C. There is equal number of each type of atom on the reactant side and product side.
The equation is equal and no material is lost or gained.
POH scale is used to measure how alkaline a solution is
pOH can be calculated as follows
pOH = - log [OH⁻]
pOH is 5.20 and using this the pH can be calculated
pOH + pH = 14
pH = 14 - pOH
pH = 14 - 5.20 = 8.80
pH scale is used to measure how acidic a solution is
pH = -log [H₃O⁺]
[H₃O⁺] = antilog (-8.80)
[H₃O⁺] = 1.6 x 10⁻⁹ M
answer is [H₃O⁺] = 1.6 x 10⁻⁹ M
Because the block of wood is more bigger and thicker
Hydrogen gas
Calcium + Water. In the following demonstration, a chunk of calcium metal is dropped into a beaker of distilled water. After a second or so, the calcium metal begins to bubble vigorously as it reacts with the water, producing hydrogen gas, and a cloudy white precipitate of calcium hydroxide.
