Gasses contain highly energetic particles which tend to spread out to fill the room/ container they are in. Often when a smell rises, there is a high concentration of gas molecules in the rising smell. Here diffusion occurs where the molecules spread out randomly moving from an area of high concentration of gas molecules to areas of low gas molecules.
Answer:
The concentration of the acid is about 0.114 M (option E)
Explanation:
Step 1: Data given
Volume of the monoprotic acid = 25.0 mL = 0.025 L
Molarity of the monoprotic acid = ?
Molarity of the NaOH solution = 0.115 M
Volume NaOH = 24.8 mL = 0.0248 L
Step 2: Calculate the concentration
a*Cb * Vb = b * Ca * Va
⇒ a = the coeficient of NaOH = 1
⇒ Cb = the molarity of the acid = TO BE DETERMINED
⇒ Vb = the volume of the acid = 0.025 L
⇒ b = the coefficient of the acid = monoprotic = 1
⇒ Ca = the moalrity of NaOH = 0.115 M
⇒ Va = the volume of NaOH = 0.0248 L
1 * Cb * 0.025 = 1 * 0.115 * 0.0248
0.025 Cb = 0.002852
Cb = 0.11408 M
The concentration of the acid is about 0.114 M
S orbital can hold 2
P can hold 6
D can hold 10
F can hold 14
Astronauts brought back 500 lb of rock samples from the moon. How many kilograms did they bring back? (1 kg = 2.20 lb)
A. 500 kg
B. 1,100 kg
C. 498 kg
D. 227 kg
I believe it is D.
Answer:
a) +640 kJ/mol or +1.06x10⁻¹⁸ J
b) +276 kJ/mol
Explanation:
To dissociate the molecule, the bond must be broken, thus, it's necessary energy equal to the energy of the bond, which can be calculated by:
E = (Q1*Q2)/(4*π*ε*r)
Where Q is the charge of the ions, ε is a constant (8.854x10⁻¹²C²J ⁻¹ m⁻¹), and r is the bond length. Each one of the ions has a charge equal to 1. The elementary charge is 1.602x10⁻¹⁹C, which will be the charge of them.
1 mol has 6.022x10²³ molecules (Avogadros' number), so the energy of 1 mol is the energy of 1 molecule multiplied by it:
E = 6.022x10²³ *(1.602x10⁻¹⁹)²/(4π*8.854x10⁻¹²*2.17x10⁻¹⁰)
E = +640113 J/mol
E = +640 kJ/mol
Or at 1 molecule: E =640/6.022x10²³ = +1.06x10⁻²¹ kJ = +1.06x10⁻¹⁸ J
b) The energy variation to dissociate the molecule at its neutral atoms is the energy of dissociation less the difference of the ionization energy of K and the electron affinity of F (EA):
498 = 640 - (418 - EA)
640 -418 + EA = 498
222 + EA = 498
EA = +276 kJ/mol
