Answer:
2.6×10^-19 J/photon
Explanation:
E of photon = h × ν
where h= 6.63 × 10^-34 j.s
v= C ÷ λ
E = ( h × c) ÷ λ
E = (6.63 × 10^-34 × 3.00
×10^8 ) ÷ ( 765 × 10^-9)
E = 2.6×10^-19 J/photon
Both litmus paper and phenolphthalein are used as acid/base (pH) indicators.
Litmus paper:
Litmus paper will turn either blue or red when a drop of solution is added to the paper. Red indicates an acidic solution (pH is <4.5), and blue indicates a basic solution (pH >8.3).
Phenolphthalein:
Phenolphthalein is commonly used during acid/base titrations. When the solution is acidic and the indicator is added, it will remain colorless. If the solution is basic, the phenolphthalein will turn pink.
The answer should be A. CaO + CO2 —> CaCO3
