Answer:
ΔE = 5.02 x 10⁻¹⁹ j
Explanation:
ΔE (photon) = h·f = (6.63 x 10⁻³⁴ j·s)(7.57 x 10¹⁴ s⁻¹) = 5.02 x 10⁻¹⁹ j
h = Planck's Constant = 6.63 x 10⁻³⁴ j·s
f = frequency (given) = 7.57 x 10¹⁴ s⁻¹
Answer:
4.07
Explanation:
There is some info missing. I think this is the original question.
<em>A solution is prepared at 25 °C that is initially 0.057 M in nitrous acid (HNO₂), a weak acid with Ka = 4.5 × 10⁻⁴, and 0.30 M in sodium nitrite (NaNO₂). Calculate the pH of the solution. Round your answer to 2 decimal places.</em>
<em />
Nitrous acid is a weak acid and nitrite (coming from sodium nitrite) is its conjugate base. Together, the form a buffer system. We can calculate its pH using the Henderson-Hasselbach equation.
pH = pKa + log [base]/[acid]
pH = -log 4.5 × 10⁻⁴ + log 0.30/0.057
pH = 4.07
Explanation:
Bayer process is industrial method of the refining of the bauxite to produce alumina which is aluminum oxide.
As alumina is amphoteric in nature, it exhibits a higher solubility at both the extremes of pH range, it is possible to dissolve alumina in low as well as in high pH solutions.
Dissolution of the alumina at high pH is well recognized in Bayer process. Bauxite is digested in very <u>high pH solution (> 13) of alkali</u> like sodium hydroxide at temperature of about 150–250°C and pressure at 20 atm. <u>This is done so that the dissolved alumina is separated from rest of insoluble bauxite minerals. </u>
Answer:
The statement is true.
Explanation:
The limiting reagent in a chemical reaction is, indeed, a substance which is completely consumed in said chemical reaction when it is done. Since the reagent is completely consumed, the amount of product is limited, due to the fact the reaction can't continue without it. So yes, it's a true statement. ;)