1answer.
Ask question
Login Signup
Ask question
All categories
  • English
  • Mathematics
  • Social Studies
  • Business
  • History
  • Health
  • Geography
  • Biology
  • Physics
  • Chemistry
  • Computers and Technology
  • Arts
  • World Languages
  • Spanish
  • French
  • German
  • Advanced Placement (AP)
  • SAT
  • Medicine
  • Law
  • Engineering
babymother [125]
3 years ago
11

Given that the rate constant is 4.0×10−4 m−1 s−1 at 25.0 ∘c and that the rate constant is 2.6×10−3 m−1 s−1 at 42.4 ∘c, what is t

he activation energy in kilojoules per mole? express your answer to three significant figures and include the appropriate units.
Chemistry
1 answer:
stepladder [879]3 years ago
4 0
So here's how you find the answer:

Given: (rate constants)

K₁ = 4.0 x 10⁻⁴ M⁻¹s⁻¹.
T₁ = 25.0 C = 293 K.
k₂ = 2.6 x10⁻³ M⁻¹s⁻¹.
T₂ = 42.4 C = 315.4 K.
R = 8,314 J/K·mol.

Use the equation:

ln(k₁/k₂) = Ea/R (1/T₂ - 1/T₁).

Transpose:

Ea = R·T₁·T₂ / (T₁ - T₂) · ln(k₁/k₂)

Substitute within the given transposed equation:

<span>Ea = 8,314 J/K·mol · 293 K · 315.4 K ÷ (293 K - 315.4 K) · ln (4.0 x 10⁻⁴ M⁻¹s⁻¹/ 2.6 x 10⁻³ M⁻¹s⁻¹).
</span>
Continuing the solution we get:

<span>Ea = 768315 J·K/mol ÷ (-22,4 K) * (-1.87)
</span>
The value of EA is:

<span>Ea = 64140.58 J/mol ÷ 1000 J/kJ = 64.140 kJ/mol.</span>


You might be interested in
What is happening to the temperature/pressure during the Deposition Change of State?
jeka94

A material will change from one state or phase to another at specific combinations of temperature and surrounding pressure. Typically, the pressure is atmospheric pressure, so temperature is the determining factor to the change in state in those cases.

Names such as boiling and freezing are given to the various changes in states of matter. The temperature of a material will increase until it reaches the point where the change takes place. It will stay at that temperature until that change is completed.


4 0
3 years ago
How many joules of heat are absorbed when 1000g of water is heated from 18Celsius to 85celsius?
o-na [289]

Answer + Explanations

Calculate heat absorption using the formula:

Q = mc∆T

Q means the heat absorbed, m is the mass of the substance absorbing heat, c is the specific heat capacity and ∆T is the change in temperature.

The heat absorbed is calculated by using the specific heat of water and the equation ΔH=cp×m×ΔT. 4. Water is vaporized to steam at 100oC. The heat absorbed is calculated by multiplying the moles of water by the molar heat of vaporization.

You can do this easily: just multiply the heat capacity of the substance you're heating by the mass of the substance and the change in temperature to find the heat absorbed.

To calculate the amount of heat released in a chemical reaction, use the equation Q = mc ΔT, where Q is the heat energy transferred (in joules), m is the mass of the liquid being heated (in kilograms), c is the specific heat capacity of the liquid (joule per kilogram degrees Celsius), and ΔT is the change in ...

Q = mc∆T. Q = heat energy (Joules, J) m = mass of a substance (kg) c = specific heat (units J/kg∙K) ∆ is a symbol meaning "the change in"

Precisely, water has to absorb 4,184 Joules of heat (1 calorie) for the temperature of one kilogram of water to increase 1°C. For comparison sake, it only takes 385 Joules of heat to raise 1 kilogram of copper 1°C.

A reaction that absorbs heat is endothermic. Its enthalpy will be positive, and it will cool down its surroundings. This reaction is exothermic (negative enthalpy, release of heat).

Quantitative experiments show that 4.18 Joules of heat energy are required to raise the temperature of 1g of water by 1°C. Thus, a liter (1000g) of water that increased from 24 to 25°C has absorbed 4.18 J/g°C x 1000g x 1°C or 4180 Joules of energy.

6 0
3 years ago
1. For each of the molecules below, determine the electron geometry, molecule geometry, and bond
Alexxx [7]

Answer:

CCl4- tetrahedral bond angle 109°

PF3 - trigonal pyramidal bond angles less than 109°

OF2- Bent with bond angle much less than 109°

I3 - linear with bond angles = 180°

A molecule with two double bonds and no lone pairs - linear molecule with bond angle =180°

Explanation:

Valence shell electron-pair repulsion theory (VSEPR theory) helps us to predict the molecular shape, including bond angles around a central atom, of a molecule by examination of the number of bonds and lone electron pairs in its Lewis structure. The VSEPR model assumes that electron pairs in the valence shell of a central atom will adopt an arrangement which tends to minimize repulsions between these electron pairs by maximizing the distance between them. The electrons in the valence shell of a central atom are either bonding pairs of electrons, located primarily between bonded atoms, or lone pairs. The electrostatic repulsion of these electrons is reduced when the various regions of high electron density assume positions as far apart from each other as possible.

Lone pairs and multiple bonds are known to cause more repulsion than single bonds and bond pairs. Hence the presence of lone pairs or multiple bonds tend to distort the molecular geometry geometry away from that predicted on the basis of VSEPR theory. For instance CCl4 is tetrahedral with no lone pair and four regions of electron density around the central atom. This is the expected geometry. However OF2 also has four regions of electron density but has a bent structure. The molecule has four regions of electron density but two of them are lone pairs causing more repulsion. Hence the observed bond angle is less than 109°.

8 0
3 years ago
Which one of the following factors would not speed up a chemical reaction?
gladu [14]
D. Making the reactant particles larger
5 0
3 years ago
Titanium and chlorine react to form titanium(IV) chloride, like this:
leva [86]

Answer:

the value of equilibrium constant for the reaction is 8.5 * 10⁷

Explanation:

Ti(s) + 2 Cl₂(g) ⇄ TiCl₄(l)

equilibrium constant Kc = \frac{1}{[Cl_2]^2}

Given that,

We are given:

Equilibrium amount of titanium = 2.93 g

Equilibrium amount of titanium tetrachloride = 2.02 g

Equilibrium amount of chlorine gas = 1.67 g

We calculate the No of mole = mass / molar mass

mass of chlorine gas = 1.67 g

Molar mass of chlorine gas = 71 g/mol

mole of chlorine = 1.67 / 71

= 7.0L

Concentration of chlorine is = no of mole / volume

= 0.024 / 7

= 3.43 * 10⁻³M

equilibrium constant Kc  = \frac{1}{[Cl_2]^2}

= \frac{1}{[3.43 * 10^-^3]^2}

= 8.5 * 10⁷

4 0
3 years ago
Other questions:
  • What is the mass of 2.25 moles of manganese(lv) sulfide(MnS2)
    8·2 answers
  • What occurs as two atoms of fluorine combine to become a molecule of fluorine?
    11·2 answers
  • Sex cells from female reproductive organ?
    7·2 answers
  • Is fire a solid liquid or gas?
    12·2 answers
  • How do isobars help meteorologists predict weather?
    13·2 answers
  • Which sequence of group 18 elements demonstrates a gradual decrease in forces of attraction
    13·1 answer
  • _____ are two or more elements that have been chemically combined. mixtures compounds atoms colloids
    7·2 answers
  • A strawberry nutritional drink used for a liquid diet is flavored with methyl butanoate. Draw the structure of methyl butanoate.
    11·1 answer
  • Balance these equations. NO LINKS!!
    10·1 answer
  • What has more heat energy, a bucket of water at 21 degrees Celsius or a swimming pool at the same temperature?
    8·1 answer
Add answer
Login
Not registered? Fast signup
Signup
Login Signup
Ask question!