Answer:
Carbon is a solid non-metal element. Carbon has eight valence electrons.
Explanation:
hope this helps!
<span>Use the van't Hoff equation:
ln
(
K2
K1
)
=
Δ
HÂş
R
(
1
T1
â’
1
T2
)
ln
(
K2
7.6*10^-3
)
=
-14,200 J
8.314
(
1
298
â’
1
333
)
ln
(
K2
7.6*10^-3
)
=
â’
1708
(
0.00035
)
ln
(
K2
0.0076
)
=
â’
0.598
Apply log rule
a
=
log
b
b
a
-0.598 =
ln
(
e
â’
0.598
)
=
ln
(
1
e
0.598
)
Multiply both sides with e^0.598
K
2
e
0.598
= 0.0076
K
e
0.598
e
0.598
=
0.0076
e
0.598
K
2
=
0.0076
e
0.598
=
4.2
â‹…
10
â’
3
K2
=
4.2
â‹…
10
â’
3</span>
Answer:
a, b, c, d
Explanation:
Rutherford’ atomic model is based on the gold foil experiment. In this experiment, beam of alpha rays was bombarded on thin gold foil. He observed that:
Most of the alpha particles passed through thin foil without any deflection.
Few alpha particles deflected by an angle of 90o.
Based on observation, Rutherford concluded that majority of the space inside the atom is empty.
He explained defection of few alpha particles by assuming that most of the mass is concentrated at the nucleus and positively charged.
Therefore, among given, the correct statements are:
The atom contains a positively charged nucleus.
Positive charge is condensed in one location within the atom.
The majority of the space inside the atom is empty space
The mass of an atom is concentrated at the nucleus
Therefore, the correct options are:
a, b, c, d
Digital offers better clarity,but analog gives you richer quality
Answer:
T = 215.33 °C
Explanation:
The activation energy is given by the Arrhenius equation:
<u>Where:</u>
k: is the rate constant
A: is the frequency factor
Ea: is the activation energy
R: is the gas constant = 8.314 J/(K*mol)
T: is the temperature
We have for the uncatalyzed reaction:
Ea₁ = 70 kJ/mol
And for the catalyzed reaction:
Ea₂ = 42 kJ/mol
T₂ = 20 °C = 293 K
The frequency factor A is constant and the initial concentrations are the same.
Since the rate of the uncatalyzed reaction (k₁) is equal to the rate of the catalyzed reaction (k₂), we have:
(1)
By solving equation (1) for T₁ we have:
Therefore, we need to heat the solution at 215.33 °C so that the rate of the uncatalyzed reaction is equal to the rate of the catalyzed reaction.
I hope it helps you!
