largest atomic radii.
Answer:
left to right across a period when it decreases and when it increases top to bottom in a group,
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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
Moles of any substance is given by the molar mass and the mass. The volume of EDTA required to titrate is 3.16 mL and the volume of zinc required to titrate is 22.8 mL.
Molarity is the property of the solution that gives the concentration of the solute present in the solution.
Given,
Mass of cobalt sulfate = 1.697 gm
The molar mass of cobalt sulfate = 155 g/mol
In the first part, the volume of the aliquot is 25 mL and the molarity is 0.08640 M.
The reaction is shown as:
Co²⁺ + H₄Y → CoH₂Y + 2H⁺
Moles of cobalt: n = 0.001694 ÷ 155 = 0.0000109 moles
In 25 ml aliquot moles of cobalt are, 0.000273 moles.
The volume of EDTA solution is calculated as:
V = moles ÷ Molarity
= 0.000273 mole ÷ 0.0864 mol/ L
= 3.16 mL
Hence, 3.16 mL of EDTA is required.
For the second part, moles of EDTA are calculated as:
n = 0.008640 × 0.050 = 4.32 ×10⁻⁴
In a 25 mL, sample moles of EDTA are 2.16 × 10⁻⁴ moles.
Excess moles of EDTA in the solution:
0.000432 - 0.000216 = 0.000216 moles
The volume of EDTA is calculated as:
V = 0.000216 ÷ 0.009450
= 0.0228 L
Hence, 22.8 mL of zinc is required.
Learn more about molarity here:
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Answer:
the answer is in the screenshot
Explanation:
hope this helps
general appearance as real-ufe
objects.
True or false
Answer:
true
Explanation:
Answer:
True
Explanation:
Because its true
Answer:
true
Explanation:
Answer:
C) Both
Explanation:
Whenever we mix any pure form of a compound with some other form of a compound which is not in the other standard pure state, this results in the melting point of mixture to get dispersed and it becomes broad form.
Thus, when a known compound of 3-Nitroaniline mixes with both 3-Nitroaniline and 4-Nitrophenol, the melting point of the compound becomes depressed and board.
Thus the correct option is (C).