The first dissociation for H2X:
H2X +H2O ↔ HX + H3O
initial 0.15 0 0
change -X +X +X
at equlibrium 0.15-X X X
because Ka1 is small we can assume neglect x in H2X concentration
Ka1 = [HX][H3O]/[H2X]
4.5x10^-6 =( X )(X) / (0.15)
X = √(4.5x10^-6*0.15)
∴X = 8.2 x 10-4 m
∴[HX] & [H3O] = 8.2x10^-4
the second dissociation of H2X
HX + H2O↔ X^2 + H3O
8.2x10^-4 Y 8.2x10^-4
Ka2 for Hx = 1.2x10^-11
Ka2 = [X2][H3O]/[HX]
1.2x10^-11= y (8.2x10^-4)*(8.2x10^-4)
∴y = 1.78x10^-5
∴[X^2] = 1.78x10^-5 m
Answer:
O.1M
Explanation:
First let's generate a balanced equation for the reaction
NaOH + HCl —>NaCl + H2O
From the equation,
The ratio of the acid to base is 1:1.
From the question, we obtained the following:
Ma = Molarity of acid = 0.12M
Va = volume of acid = 21.35cm3
Vb = volume of base = 25.55cm3
Mb = Molarity of base =?
We obtained nA(mole of acid) and nB(mole of base) to be 1
The molarity of the base can be calculated for using:
MaVa/ MbVb = nA / nB
0.12x21.35 / Mb x 25.55 = 1
Cross multiply to express in linear form
Mb x 25.55 = 0.12x21.35
Divide both side by 25.55
Mb = (0.12x21.35) / 25.55
Mb = 0.1M
The molarity of the base is 0.1M
Answer:
A. Peroxide breaking down into water and oxygen
Explanation:
Generally when it comes to changes, there are physical and chemical changes. In physical changes, there are no new substances been formed, however in chemical change new substances are formed.
A. Peroxide breaking down into water and oxygen
This is a chemical change.
B
. Bubbles forming when a pot of water is heated
This is a physical change
C. A pair of jeans soaked in water drying after hanging outside
This is a physical change
D
. A block of ice decreasing in size due to a change in temperature
This is a physical change.
Only option A is different from the rest,hence this is the answer.
Answer:
v = 2,66x10⁻⁵ P[H₂C₂O₄]
Explanation:
For the reaction:
H₂C₂O₄(g) → CO₂(g) + HCOOH(g)
At t = 0, the initial pressure is just of H₂C₂O₄(g). At t= 20000 s, pressures will be:
H₂C₂O₄(g) = P₀ - x
CO₂(g) = x
HCOOH(g) = x
P at t=20000 is:
P₀ - x + x + x = P₀+x. That means P at t=20000s - P₀ = x
For 1st point:
x = 92,8-65,8 = 27
Pressure of H₂C₂O₄(g) at t=20000s: 65,8-27 = 38,8
2nd point:
x = 130-92,1 = 37,9
H₂C₂O₄(g): 92,1 - 37,9 = 54,2
3rd point:
x = 157-111 = 46
H₂C₂O₄(g): 111-46 = 65
Now, as the rate law is :
v = k P[H₂C₂O₄]
Based on integrated rate law, k is:
(- ln P[H₂C₂O₄] + ln P[H₂C₂O₄]₀) / t = k
1st point:
k = 2,64x10⁻⁵
2nd point:
k = 2,65x10⁻⁵
3rd point:
k = 2,68x10⁻⁵
The averrage of this values is:
k = 2,66x10⁻⁵
That means law is:
v = 2,66x10⁻⁵ P[H₂C₂O₄]
I hope it helps!
Answer:
The molecular formula is C12H18O3
Explanation:
Step 1: Data given
The empirical formula is C4H6O
Molecular weight is 212 g/mol
atomic mass of C = 12 g/mol
atomic mass of H = 1 g/mol
atomic mass of O = 16 g/mol
Step 2: Calculate the molar mass of the empirical formula
Molar mass = 4* 12 + 6*1 +16
Molar mass = 70 g/mol
Step 3: Calculate the molecular formula
We have to multiply the empirical formula by n
n = the molecular weight of the empirical formula / the molecular weight of the molecular formula
n = 70 /212 ≈ 3
We have to multiply the empirical formula by 3
3*(C4H6O- = C12H18O3
The molecular formula is C12H18O3
