It is 2.51×10 to the power of 2
Answer:
1.36
Explanation:
HClO2 ⇄ H+ + ClO2-
[HClO2] [H+} [ClO2-]
initial: 0.12 0 0
change: -x +x +x
equil: 0.12-x x x
[H+][ClO2-] / [HClO2] = Ka = 1.2 * 10^-2
x* x / 0.12 - x = 1.2 * 10^-2
x^2 = (2.4 * 10^-3) - (1.2 * 10^-2)x
x^2 + (1.2 * 10^-2)x – (2.4 * 10^-3) = 0
Upon solving for x,
x = 0.04335
[H+] = 0.04335
pH = -log[H+]
pH = -log(0.04335) = - (-1.36) = 1.36
Answer : The heat of combustion of n-propanol is 0.554 kJ/mol
Explanation :
First we have to calculate the moles of n-propanol.
Molar mass of n-propanol = 60.09 g/mole
Now we have to calculate the heat of combustion of n-propanol.
As, 0.0166 mole of n-propanol liberated heat of combustion = -33.4 kJ
So, 1 mole of n-propanol liberated heat of combustion = 0.0166 × (-33.4 kJ)
= 0.554 kJ/mol
Therefore, the heat of combustion of n-propanol is 0.554 kJ/mol
Plastics, medicines and new fuels.
Answer:
manganese, Mn
Explanation:
From the question, we have;
The number of electrons in the 3d sub level = 5
The kind of element = d-block element
On the periodic table, the elements with electrons in the 3d-sublevel in increasing order are;
Sc, 3d¹ 4s²
Ti 3d² 4s²
V 3d³ 4s²
Cr 3d⁵ 4s¹
Mn 3d⁵ 4s²
Fe 3d⁶ 4s²
Co 3d⁷ 4s²
Ni 3d⁸ 4s²
Cu 3d¹⁰ 4s¹
Zn 3d¹⁰ 4s²
The elements with 5 electrons in their 3d-sublevel are chromium Cr and manganese, Mn however the electronic configuration of chromium is given as 3d⁵ 4s¹ rather than 3d⁴ 4s² due to the minor difference in the gap of energy between the 3d and the 4s orbital as such the element that has the main characteristic of 5 electrons in its 3d sub level is manganese, Mn.
