The kinetic theory states that potential energy in a gas is low but has high potential energy and they move around fast, Say in a solid it has more potential energy but less kinetic.
Answer:
Could you post another better looking question because I cannot understand this.
Explanation:
Answer:
C. CH3COOH, Ka = 1.8 E-5
Explanation:
analyzing the pKa of the given acids:
∴ pKa = - Log Ka
A. pKa = - Log (1.0 E-3 ) = 3
B. pKa = - Log (2.9 E-4) = 3.54
C. pKa = - Log (1.8 E-5) = 4.745
D. pKa = - Log (4.0 E-6) = 5.397
E. pKa = - Log (2.3 E-9) = 8.638
We choose the (C) acid since its pKa close to the expected pH.
⇒ For a buffer solution formed from an acid and its respective salt, we have the equation Henderson-Hausselbach (H-H):
- pH = pKa + Log ([CH3COO-]/[CH3COOH])
∴ pH = 4.5
∴ pKa = 4.745
⇒ 4.5 = 4.745 + Log ([CH3COO-]/[CH3COOH])
⇒ - 0.245 = Log ([CH3COO-]/[CH3COOH])
⇒ 0.5692 = [CH3COO-]/[CH3COOH]
∴ Ka = 1.8 E-5 = ([H3O+].[CH3COO-])/[CH3COOH]
⇒ 1.8 E-5 = [H3O+](0.5692)
⇒ [H3O+] = 3.1623 E-5 M
⇒ pH = - Log ( 3.1623 E-5 ) = 4.5
Answer:
541.74× 10²³ atoms of C
Explanation:
Given data:
Number of moles of carbon = 89.96 mol
Number of atoms = ?
Solution:
The given problem will solve by using Avogadro number.
It is the number of atoms , ions and molecules in one gram atom of element, one gram molecules of compound and one gram ions of a substance.
The number 6.022 × 10²³ is called Avogadro number.
1 mole = 6.022 × 10²³ atoms
89.96 mol × 6.022 × 10²³ atoms of C / 1mol
541.74× 10²³ atoms of C
Answer:
ΔT = 0.78 °C
Explanation:
Given data:
Mass of Al = 9.5 g
Specific heat capacity of Al = 0.9 J/g.°C
Temperature change = ?
Heat added = 67 J
Solution:
Formula:
Q = m.c. ΔT
Q = amount of heat absorbed or released
m = mass of given substance
c = specific heat capacity of substance
ΔT = change in temperature
67 J = 9.5 g × 0.9 j/g.°C × ΔT
67 J = 85.5 j/°C × ΔT
ΔT = 67 J / 85.5 j/°C
ΔT = 0.78 °C