Answer:
a) 1.866 × 10 ⁻¹⁹ J b) 3.685 × 10⁻¹⁹ J
Explanation:
the constants involved are
h ( Planck constant) = 6.626 × 10⁻³⁴ m² kg/s
Me of electron = 9.109 × 10 ⁻³¹ kg
speed of light = 3.0 × 10 ⁸ m/s
a) the Ek ( kinetic energy of the dislodged electron) = 0.5 mu²
Ek = 0.5 × 9.109 × 10⁻³¹ × ( 6.40 × 10⁵ )² = 1.866 × 10 ⁻¹⁹ J
b) Φ ( minimum energy needed to dislodge the electron ) can be calculated by this formula
hv = Φ + Ek
where Ek = 1.866 × 10 ⁻¹⁹ J
v ( threshold frequency ) = c / λ where c is the speed of light and λ is the wavelength of light = 358.1 nm = 3.581 × 10⁻⁷ m
v = ( 3.0 × 10 ⁸ m/s ) / (3.581 × 10⁻⁷ m ) = 8.378 × 10¹⁴ s⁻¹
hv = 6.626 × 10⁻³⁴ m² kg/s × 8.378 × 10¹⁴ s⁻¹ = 5.551 × 10⁻¹⁹ J
5.551 × 10⁻¹⁹ J = 1.866 × 10 ⁻¹⁹ J + Φ
Φ = 5.551 × 10⁻¹⁹ J - 1.866 × 10 ⁻¹⁹ J = 3.685 × 10⁻¹⁹ J
Conversion process of non-organic carbon dioxide into organic compounds by living organisms.
Example: Photosynthesis
Answer:
HCO₂
Explanation:
From the information given:
The mass of the elements are:
Carbon C = 26.7 g; Hydrogen H = 2.24 g Oxygen O = 71.1 g
To determine the empirical formula;
First thing is to find the numbers of moles of each atom.
For Carbon:
For Hydrogen:
For Oxygen:
Now; we use the smallest no of moles to divide the respective moles from above.
For carbon:
For Hydrogen:
For Oxygen:
Thus, the empirical formula is HCO₂
Answer:
E° = -0.133 V
Explanation:
In the reaction:
X(s) + Y⁺(aq) → X⁺(aq) + Y(s)
<em>1 electron is transferred from X to Y</em>
Now, using Nernst equation:
E° = RT / nF ln K
<em>Where R is gas constant (8.314 J/molK), T is absolute temperature (Usually 298.15K), n are transferred electrons (1, for the reaction), F is faraday constant (96485C/mol) and K is equilibrium constant (5.59x10⁻³)</em>
Replacing:
E° = 8.314 J/molK*298.15K / 96485C/mol*1 ln 5.59x10⁻³
<em>E° = -0.133 V</em>
