A certain first-order reaction has a rate constant of 2.10×10−2 s−1 at 19 ∘C. What is the value of k at 58 ∘C if Ea = 82.0 kJ/mol ?
Answer:
K₂ = 1.12s⁻¹
Explanation:
Based on Arrhenius equation:
ln K₂/K₁ = -Ea/R (1/T₂ - 1/T₁)
Where K is rate constant,
R is gas constant (8.314J/molK),
T is absolute temperature (In K) Of 1, initial state and 2, final state.
ln K₂/K₁ = -Ea/R (1/T₂ - 1/T₁)
ln K₂/2.10x10⁻²s⁻¹ = -82000J/mol/8.314J/molK (1/(273.15 + 58) - 1/(273.15 + 19))
ln K₂ / 2.10x10⁻²s⁻¹ = 3.976
K₂ / 2.10x10⁻²s⁻¹ = 53.3
K₂ = 1.12s⁻¹
which of the following determines an object’s ability to float in water?
a. how much the object weighs
b. what the mass of the object is
c. how dense the object is
d. the volume of the object
The density of wind-packed snow is estimated to be 0.35 g/cm^3. A flat roof that is 35 by 43 feet has 28 inches of snow on it. How many pounds of snow are on the roof?
Answer:
There are 76728.2 pounds of snow on the roof
Explanation:
To determine how many pounds of snow are on the roof,
First we will determine the mass of the snow in grams.
From the question,
Density of snow = 0.35 g/cm³
From
Density = Mass / Volume
To determine the mass, we will first find the volume.
From the question, a flat roof that is 35 by 43 feet has 28 inches of snow on it, that is, the height of the snow on the roof is 28 inches.
Area of the roof = 35 ft × 43 ft = 1505 ft²
Volume of the snow = Area of the roof × Height of the snow
Height of the snow = 28 inches
12 inches = 1 foot
∴ 28 inches = 28/12 feet = 2.3333 ft
Hence,
Volume of the snow = 1505 ft² × 2.3333 ft = 3511.62 ft³
Volume of the snow = 3511.62 ft³
This is the volume of the snow in cubic feet
Now, we will convert cubic feet (ft³) to cubic centimeter (cm³)
1 ft = 30.48 cm
and 1 ft³ = 30.48³ cm³ = 28316.84659 cm³.
If 1 ft³ = 28316.84659 cm³
∴ 3511.62 ft³ will be 3511.62 × 28316.84659 cm³ = 99438004.83 cm³
Hence, Volume of snow = 99438004.83 cm³
Now, we can determine mass of snow in grams
From
Density = Mass / Volume
Mass = Density × Volume
Mass = 0.35 g/cm³ × 99438004.83 cm³
Mass = 34803301.69 g
Now, we will convert the mass from grams to pounds
1 pound = 453.592 grams
If 453.592 grams = 1 pound
Then, 34803301.69 g will be 34803301.69 / 453.592 pounds = 76728.2 pounds
Hence, there are 76728.2 pounds of snow on the roof.
For a water in equilibrium with the atmosphere, a pH of 2.0, and a total soluble iron concentration of 1 mg/L, calculate the concentrations of Fe2+(aq) and Fe3+(aq).
Answer:
Fe^2+(aq) = 4.51 × 10^-11 M
Fe3+(aq) = 1.79 × 10^5 M.
Explanation:
So, the first thing to do is to to write out the chemical reaction showing the ionic reaction of the chemical species present in the chemical reaction;
4Fe^2+ (aq) + O2(g) + 4H^+ <---------------------------> 4Fe^3+(aq) + 2H2O(l).
The next thing to do is to determine or calculate for G° and the equilibrium constant,kc. Thus, the value of G° = 4(-4.6) + 2(-237.18) - {4(-78.87)} = -177.28 kJ/mol.
Therefore, the equilibrium constant = e^-∆G°/RT = 1.19 × 10^31.
Therefore the value for Fe^2+ and Fe^3+ can be determine as;
NB=> Recall that [Fe^3+]/[Fe^2+] = kc [(Po2) (H^+)^4]^1/4.
Also, 1/ 55850 = 1.79 × 10^-5 M.
[Fe^2+] + [Fe^3+] = 1.79 × 10^-5. -------(1).
Therefore, [Fe^3+]/[Fe^2+] = kc [(Po2) (H^+)^4]^1/4. = [Fe^3+]/[Fe^2+] = [ 1.19 × 10^31 × 0.2095 × (10^2)^2] ^1/4 = 3.97 × 10^5.
Therefore, [Fe^3+]/[Fe^2+] = 3.97 × 10^5.
[Fe^3+] = 3.97 × 10^5[Fe^2+].
Hence, using the equation (1) above we can determine the value of the species.
[Fe^2+] + [Fe^3+] = 1.79 × 10^-5
[Fe^2+] + [Fe^2+] = 1.79 × 10^-5.
[Fe^2+] + 3.97 × 10^5[Fe^2+] = 1.79 × 10^-5.
[Fe^2+] = 4.51 × 10^-11 M.
Therefore, we will have [Fe^3+]/[Fe^2+] = 3.97 × 10^5.
Thus, [Fe^3+] = [Fe^2+] × 3.97 × 10^5. = 1.79 × 10^5 M.
How many moles of each substance is produced when 7 moles of ammonium carbonate decompose?
(NH4)2CO3(s) ⟶ NH3(g) + CO2(g) + H2O(g)
Answer:
1. 14 moles of NH3 were produced.
2. 7 moles of CO2 were produced.
3. 7 moles of H2O were produced.
Explanation:
We'll begin by writing a balanced equation for the decomposition of ammonium carbonate, (NH4)2CO3.
This is illustrated below:
(NH4)2CO3(s) —> NH3(g) + CO2(g) + H2O(g)
There are 2 atoms of N on the left side and 1 atom on the right side. It can be balance by putting 2 in front of NH3 as shown below:
(NH4)2CO3(s) —> 2NH3(g) + CO2(g) + H2O(g)
Now the equation is balanced.
From the balanced equation above,
1 mole of (NH4)2CO3 decompose to produce 2 moles of NH3, 1 mole of CO2 and 1 mole of H2O.
1. Determination of the number of mole of NH3 produced.
From the balanced equation above,
1 mole of (NH4)2CO3 decompose to produce 2 moles of NH3.
Therefore, 7 moles of (NH4)2CO3 will decompose to produce = 7 × 2 = 14 moles of NH3.
Therefore, 14 moles of NH3 were produced.
2. Determination of the number of mole CO2 produced.
From the balanced equation above,
1 mole of (NH4)2CO3 decompose to produce 1 mole of CO2.
Therefore, 7 moles of (NH4)2CO3 will also decompose to produce 7 moles of CO2.
Therefore, 7 moles of CO2 were produced.
3. Determination of the number of mole of H2O produced.
From the balanced equation above,
1 mole of (NH4)2CO3 decompose to produce 1 mole of H2O.
Therefore, 7 moles of (NH4)2CO3 will also decompose to produce 7 moles of H2O.
Therefore, 7 moles of H2O were produced.
A 25.00-mL aliquot of a nitric acid solution of unknown concentration is pipetted into a 125-mL Erlenmeyer flask and 2 drops of phenolphthalein are added. The above sodium hydroxide solution (the titrant) is used to titrate the nitric acid solution (the analyte). If 12.75 mL of the titrant is dispensed from a burette in causing a color change of the phenolphthalein, what is the molar concentration of the nitric acid solution? (Show all steps for calculating the answer.)
Answer: 0.0611 M HNO3
Answer:
0.0611M of HNO3
Explanation:
The concentration of the NaOH solution must be 0.1198M
The reaction of NaOH with HNO3 is:
NaOH + HNO3 → NaNO3 + H2O
1 mole of NaOH reacts per mole of HNO3.
That means the moles of NaOH used in the titration are equal to moles of HNO3.
Moles HNO3:
12.75mL = 0.01275L * (0.1198mol / L) = 0.0015274 moles NaOH = Moles HNO3.
In 25.00mL = 0.025L -The volume of the aliquot-:
0.00153 moles HNO3 / 0.025L =
0.0611M of HNO33. Does matter increase in
mass when mixed with
another substance?
a Yes
b. No
Answer:
b. No
Explanation:
The question above is related to "The Law of Conservation of Mass." This law states that mass is neither created nor can it be destroyed. Even if a particular matter will be mixed with another substance or it undergoes chemical reaction, the mass of the matter will remain the same. Even with a change in phase, the mass of the matter will remain the same.
Someone plz hello me ASAP it would be appreciated on question 7 btw
Answer:
Kinetic Energy is the correct Answer.
Explanation:
At the highest point on the roller coaster (assuming it has no velocity), the object has a maximum quantity of gravitational potential energy. As the object begins moving down to the bottom, its gravitational potential energy begins to decrease and the Kinetic Energy starts to increase.
identify which statement is true
Answer:
I'm sorry to say but there is no statements in this question meaning no one will be able to answer them with out them.. what are the statements?
Explanation:
1.191 mol N2O3 is put into a 2.00 L flask at 25°C where it decomposes into NO2(g) and NO(g). What is the equilibrium constant (to 4 decimal places) if the reaction mixture contains 0.300 mol NO2 at equilibrium?
Answer:
K = 0.0505
Explanation:
Based on the equilibrium:
N2O3 ⇄ NO2 + NO
K, equilibrium constant, is defined as:
K = [NO2] [NO] / [N2O3]
Where [] are the equilibrium concentration of each species in the mixture.
The initial molarity of N2O3 is:
1.191mol / 2.00L = 0.5955M
In equilibrium, 0.5955M of N2O3 reacts producing X Molar of NO2 and X Molar of NO:
[N2O3] = 0.5955M - X
[NO2] = X
[NO] = X
As equilibrium concentration of NO2 is 0.300mol/2.00L = 0.15M; X = 0.15M:
[N2O3] = 0.5955M - 0.15M = 0.4455M
[NO2] = 0.15M
[NO] = 0.15M
And K is:
K = [0.15M] [0.15M] / [0.4455M]
K = 0.0505
what is the relationship between the atomic number and the melting and boiling point
Answer:
As the atomic number of elements increases, the melting point increases because there are more electrons around the nucleus, which creates a stronger negatively-charged force. With stronger forces, the melting point rises. 3. Non-metals usually have low melting points.
Explanation:
The melting point rises as the atomic number of elements increases because there are more electrons surrounding the nucleus, creating a stronger negatively charged force. The melting point rises as the forces become stronger.
What is nucleus?The nucleus is made up of protons, which are positively charged, and neutrons, which are electrically neutral. Quarks are particles that make up protons and neutrons. The nucleus (plural, nuclei) is a positively charged region in the atom's center. It is made up of two types of subatomic particles that are tightly packed together. Protons, which have a positive electric charge, and neutrons, which have a neutral electric charge, are the particles. The nucleus is the most important component of the cell (plural: nuclei). It is derived from a Latin word that means "nut kernel." Definition of Nucleus: A nucleus is a double-membraned eukaryotic cell organelle that contains genetic material.To learn more about nucleus, refer to:
https://brainly.com/question/14110259
#SPJ2
he concentration of H2S in a saturated aqueous solution at room temperature is approximately 0.1 M. Ka1=8.9x10-8 Ka2=1.0x10-19 Calculate the pH of the solution in 2 sig figs
Answer:
PH = 4.0
Explanation:
We are given;
Ka1 = 8.9 × 10^(-8)
Ka2 = 1.0 × 10^(-19)
From the 2 values of K given above, we can see that Ka2 is far smaller than Ka1.
Thus, Positive hydrogen ion (H+) will be majorly formed from first dissociation which is Ka1.
Now, the breakdown of the H2S solution is;
H2S⇌[H+] + [HS−]
Thus;
Ka1 = [[H+] × [HS2^(-)]]/(H2S)
HS2^(-) also has a positive hydrogen ion.
Thus, we can rewrite as;
Ka1 = [[H+] × [H+]]/(H2S)
Ka1 = (H+)²/(H2S)
Concentration of H2S is given as 0.1M. Thus;
8.9 × 10^(-8) = (H+)²/0.1
(H+)² = 0.1 × 8.9 × 10^(-8)
(H+) = √(0.1 × 8.9 × 10^(-8))
(H+) = 0.00009433981
Now, PH is gotten from;
PH = -log (H+)
Thus;
PH = -log 0.00009433981
PH ≈ 4.0
Two fruit flies that are heterozygous for body color and eye color are crossed. Brown body color is dominant to black body color. Red eye color is dominant to brown eye color.
Determine the genotypes of offspring 1-8.
1
2
3
4
5
6
7
8
A 4-column table has 4 rows. The labels of the columns are Upper B Upper E, Upper B e, b Upper E, b e. The labels of the rows are Upper B Upper E, Upper B e, b Upper E, Upper B b Upper E e. The first column has entries 1, Upper B Upper B Upper E e, 4, Upper B b Upper E e. The second column has entries Upper B Upper B Upper E e, 3, Upper B b Upper E e, 7. The third column has entries Upper B b Upper E Upper E, Upper B b Upper E e, 5, b b Upper E e. The fourth column has entries 2,Upper B b e e, 6, 8.
Answer:
the answer is simple
Explanation:
jnnn B upper up of the eye color
Answer:
1. BBEE
2. BbEe
3. BBee
4. BbEE
5. bbEE
6. bbEe
7. Bbee
8.bbee
explain the reason each step of the separation is performed with three portions of the solvent rather than with a single poriton of solvent
Answer:
Several extractions is more effective than a single extraction.
Explanation:
When extraction is carried out multiple times, for instance, in this case, the extraction was carried out with three portions of the solvent rather than with just a single portion of the solvent, the amount of material left in the residue will be lower, because the extraction is more complete.
Several extractions with smaller volumes of solvent are more effective than a single extraction with a large volume of solvent.
What does this image represent?
a) alcohol group
b) carbonyl group
c) ether group
d) hydroxyl group
Explanation:
It represent Alcohol group (—OH)
Convert
12 x 1025 kg/mL to fg/cm3
Answer:
[tex]1.2x10^{38}\frac{fg}{cm^3}[/tex]
Explanation:
Hello there!
In this case, for such unit conversion we need to realize that 1 kg is equal to 1000 g, 1 g is equal to 1x10⁹ and 1 mL equals 1 cm³, therefore we apply:
[tex]12x10^{25}kg*\frac{1000g}{1kg} *\frac{1x10^9fg}{1g} *\frac{1mL}{1cm^3} \\\\1.2x10^{38}\frac{fg}{cm^3}[/tex]
Best regards!
Which is one way that minerals crystallize from materials dissolved in water?
from the air
from solutions that evaporate
from hot water solutions when water boils
from the soil
Answer:
the second answer its science behind it
Answer:
b
Explanation:
Why is energy involved in changes of state?
Answer:
The energy of particles of matter determines the matter's state. Particles of a gas have more energy than particles of a liquid, and particles of a liquid have more energy than particles of a solid. Therefore, in order for matter to change from a solid to a liquid or from a liquid to a gas, particles of matter must absorb energy. In order for matter to change from a gas to a liquid or from a liquid to a solid, particles of matter must lose energy.
The system will lose or gain energy as a result of changing its state, which is why energy will be involved in state changes.
What is energy?
Energy is a quantitative property that would be transferred to a body or even a physical system and is visible in term of heat as well as light during the performance of work.
Whenever a state changes, energy is involved. When matter transitions through one state to another, it either releases or absorbs energy. When matter transforms from such a liquid to a solid, for example, it loses energy. When matter transforms from a solid to a liquid, the opposite occurs.
To know more about energy.
https://brainly.com/question/1932868.
#SPJ2
3. Which of the following molecules would want except to have a nonpolar covalent bond
Answer:
polar bonds are caused by different kind of atoms, because almost every atoms have different powers to attract electrons.
the answer will be the two same atoms, F2
A tank at is filled with of dinitrogen difluoride gas and of chlorine pentafluoride gas. You can assume both gases behave as ideal gases under these conditions. Calculate the mole fraction and partial pressure of each gas, and the total pressure in the tank. Be sure your answers have the correct number of significant digits.
The question is incomplete, the complete question is;
A 8.00 L tank at 2.64 °C is filled with 9.82 g of chlorine pentafluoride gas and 10.1 g of dinitrogen difluoride gas. You can assume both gases behave as ideal gases under these conditions. Calculate the mole fraction and partial pressure of each gas, and the total pressure in the tank. Be sure your answers have the correct number of significant digits.
Answer:
See explanation for details
Explanation:
Number of moles of N2F2 = mass/ molar mass
Molar mass of N2F2 = 66 g/mol
Number of moles = 10.1 g/66 = 0.15 moles
Number of moles of ClF5 = 9.82 g/130 g/mol= 0.08 moles
Molar mass of ClF5= 130g/mol
Total number of moles = 0.15 moles + 0.08 moles = 0.23 moles
Given that;
T= 2.64 °C + 273 = 275.64 K
n= 0.23 moles
R= 0.082 Latmmol-1K-1
V= 8.00 L
P= ??
From;
PV =nRT
P= nRT/V
P= 0.23 ×0.082 × 275.64/8.00
P= 0.65 atm
Mole fraction of N2F2= 0.15/0.23 = 0.65
Partial pressure = mole fraction × total pressure = 0.65 × 0.65 = 0.42 atm
Mole fraction of ClF5 = 0.08/0.23 = 0.35
Partial pressure of ClF5 = mole fraction × total pressure = 0.35 × 0.65 = 0.22 atm
Why is Newton's 1st Law also known as the Law of Inertia?
Answer:
Law of Inertia it's also called Newton's first law of motion simply stated it means an object in motion tends to stay in motion or an object at rest tends to stay at rest unless the object is acted upon by an unbalanced force. Hope this helped!
Answer:
It means an object in motion tends to stay in motion or an object at rest tends to stay at rest unless the object is acted upon by an unbalanced force.
When methylcyclobutane is treated with chlorine gas and heated, the total number of monochlorinated products, including stereoisomers, is
Answer:
5
Explanation:
The image attached shows the different monochlorination products obtained when chlorine gas is heated with methylcyclobutane.
We must keep in mind that the reaction occurs by free radical mechanism as shown in the image attached. The proportion in which the products are formed depends on the stability of the free radical intermediate leading to that particular product.
Image credit: askiitians
Which of the following is NOT an example of deposition?
sand dune
river delta
cave crystal
valley
This science btw
Answer:
Cave Crystal
Explanation:
I believe it's cave crystal because sand dunes, river deltas, and valleys are all examples of deposition.
The first energy level which has p orbitals to fill is ___
1
2
3
4
Answer:
2
Explanation:
The Aufbau sequence of increasing energy levels is 1s,2s,2p,3s,3p,4s,3d and so on....
Hope this helps! :D
Which of the following particles combine to form molecules?
Compounds
Protons
Electrons
Atoms
Answer: i think its protons and electrons but it also might just be atoms because protons and electrons make atoms when there are also neutrons
Explanation:
Which condition produces an anion?
A. more neutrons than electrons
B. more protons than electrons
C. more electrons than neutrons
D. more electrons than protons
What is the momentum of a 1kg ball moving at 5m/s?
Answer:
5Ns
momentum= mass *velocity
=1*5
=5Ns
Someone plz hello me ASAP it would be appreciated on question 2 and 3 btw
Answer:
2 should be potential energy and 3 should be A
Explanation:
ou are given a solution containing a pair of enantiomers (A and B). Careful measurements show that the solution contains 98% A and 2% B. What is the ee of this solution
Complete Question
You are given a solution containing a pair of enantiomers (A and B). Careful measurements show that the solution contains 98% A and 2% B. What is the enantiomeric excess?
Answer:
The value is [tex]k = 96 %[/tex]
Explanation:
From the question we are told that
The percentage of enantiomer A is A = 98%
The percentage of enantiomer B is B = 2%
Generally the enantiomeric excess is mathematically represented as
[tex]k = \frac{A -B}{A+B} * 100[/tex]
=> [tex]k = \frac{98 -2}{98+2} * 100[/tex]
=> [tex]k = 96 %[/tex]
Calculate the pH of a 0.02 M solution of ascorbic acid ( K a1 = 7.9 × 10 –5; K a2 is 1.6 × 10 –12).
a.
2.9
b.
8.2
c.
11.8
d.
11.1
e.
5.8
Answer:
C
Explanation: