Answer:
7.4 - 5.4.
Explanation:
The relationship between HIn that is the non-ionized form and the In^-; the ionized form is an equilibrium Reaction which is given below;
HIn(aq) + H2O(l) <--------> H3O^+(aq). + In^-(aq).
From the question, we are given that the ka is 4 ×10^−7, therefore, the mathematical relationship between HIn and In^- is given below;
Ka = [H3O^+] [In^-] / [HIn] = 4 ×10^−7.
The formula we are going to be using to solve this question is given below;
pH = pKa (+ or -) 1.
Recall that the relationship between the ka and pKa;
pKa = - log (ka).
pKa = - log ( 4 ×10^−7).
pKa = 6.4
Therefore, for it to have a distinct color change, the pH range will be;
pH = pKa (+ or -) 1.
pH= 6.4 + 1 = 7.4.
pH= 6.4 - 1 = 5.4.
Hence, the pH range = 7.4 - 5.4.
The brain stem connects the brain with the spinal cord. It controls hunger and thirst and some of the most basic body functions, such as body temperature, blood pressure, and breathing. The brain is protected by the bones of the skull and by a covering of three thin membranes called meninges.
Answer:
r = k × [A] × [B]
Explanation:
To determine the rate law, we simply use the slow step reaction equation. The slow step is the rate determining step in the reaction.
A+B→AB
And as we know, the rate of the reaction is proportional directly to the product of the concentration of the reactants which concentration is changing over the course of the reaction.
r = k × [A] × [B]
Where r = rate of reaction
k = reaction rate constant
[A] = Concentration of molecule A
[B] = Concentration of molecule B
Metal conductivity generally goes down or resistivity goes up with temperature goes up.
Answer:
1.63ₓ10⁻⁶ g of U
139.03 g of H
0.385 g of O
141.8 g of Pb
Explanation:
In first place, we need to convert the number of atoms to moles, as we know that 1 mol of anything occupies 6.02×10²³ particles
Therefore:
4.12×10¹⁵ atoms of U . 1 mol / 6.02×10²³ atoms = 6.84×10⁻⁹ moles of U
8.37×10²⁵ atoms of H . 1 mol /6.02×10²³ atoms = 139.03 moles of H
1.45×10²² atoms of O . 1 mol /6.02×10²³ atoms = 0.0241 moles of O
4.12×10²³ atoms of Pb . 1 mol /6.02×10²³ atoms = 0.684 moles of Pb
Moles . Molar mass = Mass (g)
6.84×10⁻⁹ moles of U . 238.03 g/mol = 1.63ₓ10⁻⁶ g of U
139.03 moles of H . 1 g/mol = 139.03 g of H
0.0241 moles of O . 16 g/mol = 0.385 g of O
0.684 moles of Pb . 207.2 g/mol = 141.8 g of Pb
