True, because most chemical reactions have more moles but not really.
Also that they decompose better. "not really"
Answer:
a
No
b
100 mm Hg
Explanation:
From the question we are told that
The vapor pressure of CHCl3, is 
The temperature of CHCl3 is 
The volume of the container is 
The temperature of the container is 
The mass of CHCl3 is m = 0.380 g
Generally the number of moles of CHCl3 present before evaporation started is mathematically represented as
Here M is the molar mass of CHCl3 with the value 
=> 
=> 
Generally the number of moles of CHCl3 gas that evaporated is mathematically represented as
Here R is the gas constant with value 
So
Given that the number of moles of CHCl3 evaporated is less than the number of moles of CHCl3 initially present , then it mean s that not all the liquid evaporated
At equilibrium the temperature of CHCl3 will be equal to the pressure of air so the pressure at equilibrium is 100 mmHg
Answer: The mass of electrons is mostly ignored because electrons are extremely small compared to neutrons and protons.
Explanation: A proton is about 1,836 times the size of an electron.
On the periodic table, the atomic number for each element can be found. This number is found by measuring the weight of 6.02 x 10^23 atoms of the element in grams. Electrons aren't ignored when finding exact math, but for the sake of simplification high school teachers will generally have you only count the number of protons and neutrons when calculating the mass of atoms.
Answer:
a. 1.78x10⁻³ = Ka
2.75 = pKa
b. It is irrelevant.
Explanation:
a. The neutralization of a weak acid, HA, with a base can help to find Ka of the acid.
Equilibrium is:
HA ⇄ H⁺ + A⁻
And Ka is defined as:
Ka = [H⁺] [A⁻] / [HA]
The HA reacts with the base, XOH, thus:
HA + XOH → H₂O + A⁻ + X⁺
As you require 26.0mL of the base to consume all HA, if you add 13mL, the moles of HA will be the half of the initial moles and, the other half, will be A⁻
That means:
[HA] = [A⁻]
It is possible to obtain pKa from H-H equation (Equation used to find pH of a buffer), thus:
pH = pKa + log₁₀ [A⁻] / [HA]
Replacing:
2.75 = pKa + log₁₀ [A⁻] / [HA]
As [HA] = [A⁻]
2.75 = pKa + log₁₀ 1
<h3>2.75 = pKa</h3>
Knowing pKa = -log Ka
2.75 = -log Ka
10^-2.75 = Ka
<h3>1.78x10⁻³ = Ka</h3>
b. As you can see, the initial concentration of the acid was not necessary. The only thing you must know is that in the half of the titration, [HA] = [A⁻]. Thus, the initial concentration of the acid doesn't affect the initial calculation.
<h3>
Answer:</h3>
Balanced equation: 4Fe + 3O₂ → 2Fe₂O₃
Moles of oxygen gas = 9 moles
<h3>
Explanation:</h3>
To answer the question;
- We first write the balanced equation between iron metal and Oxygen
- The balanced equation is given as;
4Fe + 3O₂ → 2Fe₂O₃
- We are given 6 moles of Fe₂O₃
We are required to determine the number of moles of oxygen needed to form 6 moles of Fe₂O₃.
- From the equation, 3 moles of oxygen gas reacts to produce 2 moles of Fe₂O₃
- This means, the mole ratio of O₂ to Fe₂O₃ is 3 : 2
Therefore; Moles of O₂ = Moles of Fe₂O₃ × 3/2
Hence, moles of oxygen = 6 moles × 3/2
= 9 moles
Thus, Moles of Oxygen needed is 9 moles
