Answer:
32
Explanation:
The 1995 Nobel Prize in Chemistry was shared by Paul Crutzen, F. Sherwood Rowland, and Mario Molina for their work concerning the formation and decomposition of ozone in the stratosphere. Rowland and Molina hypothesized that chlorofluorocarbons (CFCs) in the stratosphere break down upon exposure to UV radiation, producing chlorine atoms. Chlorine was previously identified as a catalyst in the breakdown of ozone into oxygen gas. Using the enthalpy of reaction for two reactions with ozone, determine the enthalpy of reaction for the reaction of chlorine with ozone.
ClO(g)+O3(g)â¶Cl(g)+2O2(g) ÎHârxn=â122.8 kJ
2O3(g)â¶3O2(g) ÎHârxn=â285.3 kJ
O3(g)+Cl(g)â¶ClO(g)+O2(g) ÎHârxn= ?
Answer:
ΔH = -162.5 kJ.
Explanation:
Hello.
In this case, we first rearrange the reactions:
ClO(g) + O₃(g) ⇒ Cl(g) + 2O₂(g); ΔH =-122.8 kJ
2O₃(g) ⇒ 3O₂(g); ΔH=-285.3 kJ
O₃(g) + Cl(g) ⇒ ClO(g) + O₂(g); ΔH= ?
Thus, we are going to use the Hess law, as an strategy to rearrange the known chemical reactions and thereby compute the enthalpy of reaction of the unknown one.
1. The first reaction must be inverted in order to obtain chlorine as a reactant in the third one, therefore, the enthalpy of reaction becomes positive:
Cl(g) + 2O₂(g) ⇒ ClO(g) + O₃(g); ΔH = 122.8 kJ
2. Second reaction remains the same:
2O₃(g) ⇒ 3O₂(g); ΔH=-285.3 kJ
Then, we add them to obtain:
Cl(g) + 2O₂(g) + 2O₃(g) ⇒ ClO(g) + O₃(g) + 3O₂(g)
Whereas we can subtract both oxygen and ozone to obtain the third one:
O₃(g) + Cl(g) ⇒ ClO(g) + O₂(g)
Therefore, the enthalpy of reaction turns out:
ΔH = 122.8 kJ + (-285.3 kJ )
ΔH = -162.5 kJ.
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(2.6 x 10^6) / (2.0 x 10^8)
Answer:
0.013
Explanation:
50 POINTS
When air heats up, it will _____, cool, and then _____ back down. The creates a convection cell.
1. heat ; fall
2. condense ; fall
3. fall ; rise
4. rise ; fall
Answer:
rise the fall
Explanation:
when air is heated it become lighter then rise but when cooled it becomes heavy and fall
What do hurricanes, tornadoes, and thunderstorms have in common?
Answer choices: cold temperatures
low pressure systems
storm surge
precipitation
Answer:
What do hurricanes, tornadoes, and thunderstorms have in common?
ANSWER : Low pressure systems
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Heather mixes two white liquids together. Immediately, a gray liquid forms.
How is the gray liquid related to the white liquids?
ОА
There is no relationship between the gray liquid and white liquids.
B
The gray liquid was released from inside the atoms of the white liquids.
С
The gray liquid is made up of the same kinds of atoms as the white liquids, but the atoms are arranged differently.
D
The gray liquid is made up of the same kinds of molecules as the white liquids, but the molecules are a different color.
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O
Answer:
A is the correct answer
How many moles of sodium sulfate will be produced from 25.6 grams of sodium hydroxide? Moles to sodium sulfate to mol
es una muy buena experiencia para poder conseguir una buena respuesta
nuclear equation of Rn-220 alpha decay
What do Px Pz and Py represent.
Answer:
Explanation:
The names Px, Py and Pz, indicate the orientation of the orbital in space. The key difference between Px Py and Pz orbitals is that Px orbital has two lobes oriented along the x-axis and Py orbital has two lobes oriented along the y-axis whereas Pz orbital has two lobes oriented along the z-axis.
Answer:
Px can stand for Picture Pixel Prescription Prognosis Post Exchange or Physical Exam Personal Exchange Price.
Pz can stand for Precautionary Zone
Py can stand for Program Year or Python
Explanation:
hope this helps
1-isopropyl-2-methylcyclohexane identify the numbers of hydrogen atoms
Explanation:
I think 20
0 in the photo should be 1, 1, 1
In 1-isopropyl-2-methylcyclohexane, the number of hydrogen atoms is 18, and this is also an isomer of the cyclohexane, there is a methyl group on the first carbon and an isopropyl group on the second carbon in 1-isopropyl-2-methylcyclohexane.
What is the significance of 1-isopropyl-2-methylcyclohexane?It is significant as it has a methyl group and an isopropyl group, it is an isomer of the cyclohexane, and it is a compound that can exist in multiple forms with different properties, such as in the field of organic chemistry, uses in industry, etc.
Hence, in 1-isopropyl-2-methylcyclohexane, the number of hydrogen atoms is 18, and this is also an isomer of the cyclohexane, there is a methyl group on the first carbon and an isopropyl group on the second carbon in 1-isopropyl-2-methylcyclohexane.
Learn more about methylcyclohexane here.
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What is the temperature shown on the thermometer below?
A. 8 °F
B. 4 °F
C. –4 °F
D. –8 °F
Why is this important in chemistry to balance equations?
Answer:
The bonds between atoms in the reactants are rearranged to form new compounds in chemical reactions, but none of the atoms disappear and no new ones are formed. As a consequence, chemical equations must be balanced, meaning that the number and kinds of atoms must be the same on both sides of the reaction arrow.
Answer:
The Law of Conservation of Mass states that mass is neither created nor destroyed, it only changes.
So when you balance a chemical equation, what you get is the same equation, but with the same number of atoms of each chemical element in the reactants and in the products. In this way the conservation of mass is achieved, because the same number of atoms that exists in the reactants is the one that is later transformed and appears in the products.
A balanced equation is the following:
H2 + 1/2O2 --------> H2O
Reactants: Products:
Amount of H = 2 Amount of H = 2
Amount of O = 1 Amount of O = 1
It is a balanced equation because each element has the same number of atoms in the reactants and in the products.
Explanation:
If I help you give me points, thanks.
What the rows of elements in the periodic table called?
A: orbitals
B: s, p, d, and f blocks
C: periods
D: groups
A certain element has 12 neutrons and 12 protons. Assume that this atom has an
overall neutral charge.
What is the identity of this element?
Which relationship is present in a solution that has a pH of 7
Answer:
neutral
Explanation:
pH is usually (but not always) between 0 and 14. Knowing the dependence of pH on [H +], we can summarize as follows: If pH < 7, then the solution is acidic. If pH = 7, then the solution is neutral
Use the drop-down menus to indicate the stage of technological design in which each action would occur
Answer:
Explanation:
whats the thing to put 2 gether
Calculate the volume occupied by 1.68 g of He gas at STP.
Answer:
Explanation:
It can be written as: V = nRT/P. "P" is pressure, "V" is volume, n is the number of moles of a gas, "R" is the molar gas constant and "T" is temperature. Record the molar gas constant "R". R = 8.314472 J/mole x K.
Explain the difference between a working theory and a paradigm? PLEASE ANSWER QUICK I WILL MARK BRAINLIEST
Answer: The theory explains the phenomenon based on certain criteria while the paradigm provides the background or the frame that allows a theory to be tested and measured.
Explanation:
Bombarding plutonium-239 with an alpha particle creates an isotope of curium. Balance the equation. 239 94 Pu + 4 2 He → a b Cm + c d n Identify the values for the unknown letters. a is b is c is d is
Answer:
242
96
1
0
Explanation:
Knowing the functioning of balancing equations, we have that the values of the constants correspond to 242, 96, 1 e 0.
Given the equation we have:
[tex]239 \ 94 Pu + 4 2 He \rightarrow a b Cm + c d[/tex]
Knowing from the beginning that nothing is lost and nothing is created but everything is transformed, we will have that the value of the constants will be given by:
D: will be equal to zero because two constants together don't mean anythingC: will be equal to 1 for the same reason as D.so for a and b we will calculate as:
[tex]239+3=a\\a=242\\94+2=b\\b=96[/tex]
See more about balancing equations at brainly.com/question/10413253
A chemist uses atomic absorption spectroscopy to measure the amount of calcium in a urine sample. When preparing the sample for analysis, the chemist adds an excess of La3 to the sample. Why is La3 added to the urine sample
Answer: La+3 binds to PO4-3 in the urine sample which prevents the formation of Ca3(PO4)2 and frees the Ca+2 in the sample to be atomized.
Explanation:
In the presence of phosphates, the calcium ions form a refractory compound (calcium phosphate) which is not atomized in the plasma/flame in atomic absorption spectroscopy.
The addition of a releasing agent like lanthanum to the sample minimizes the formation of refractory compounds as the lanthanum binds with the phosphate ions to form more volatile compounds.
You are given a sulfuric acid solution of unknown concentration. You dispense 10.00 mL of the unknown solution into an Erlenmeyer flask and add 12.2 mL of distilled water and a drop of phenopthalein to the flask. You fill your buret with 0.103 M NaOH (aq) solution and begin the titration. During the titration you rinse the tip and the sides of the Erlenmeyer flask with 3.52 mL of distilled water. It requires 10.38 mL of your NaOH (aq) solution to reach the endpoint and a very faint pink color in the flask. What is the concentration of your sulfuric acid solution in M (Remember the balanced equation for this reaction)?
Answer:
"0.053457 M" of sulfuric acid.
Explanation:
The given values are:
[tex]V[/tex] = 10 mL solution
[tex]V_{added}[/tex] = 12.20 mL
[tex]V_{total}[/tex] = 22.20 mL
then,
M 0.103 M of NaOH,
[tex]V_{rinsed}[/tex] = experiment will not be affected
[tex]V_{total \ base}[/tex] = 10.38 mL
Now,
⇒ mol of NAOH = MV
= [tex]0.103\times 10.38[/tex]
= [tex]1.06914 \ m[/tex]
Whether Sulfuric acid, then
⇒ [tex]H_{2}SO_{4} + 2NaOH = Na_{2}SO_{4} + 2H_{2}O[/tex]
⇒ [tex]mol \ of \ acid =\frac{1}{2}\times \ mol \ of \ base[/tex]
⇒ [tex]1.06914 \ m \ mol \ of \ base = \frac{1}{2}\times 1.06914 = 0.53457 \ m \ mol \ of \ acid[/tex]
Before any dilution:
[tex]V_{sample} = 10 \ mL[/tex]
⇒ [tex]M \ acid = \frac{m \ mol}{V}[/tex]
[tex]=\frac{ 0.53457 }{10}[/tex]
[tex]=0.053457 \ M[/tex] (Sulfuric acid)
6. Macromolecules represent which level of organization in the body?
cellular
tissue
o
chemical
organ
Answer:
Chemical
Explanation:
Macromolecules are part of the chemical components of cells. For example, DNA, proteins, and lipids.
Cells of similar types/function form tissues. Different types of tissues interact together to form organs. Organs form a common function.
All of the rocks in the world used to be _________________ rock called molten rock.
Copper reacts with silver nitrate to produce silver and
copper(ll) nitrate. In this reaction 40.7 g of silver is produced.
g
Calculate number of moles of each reactant.
Answer:
0.188 moles of copper and 0.376 moles of silver nitrate
Explanation:
hope this helps
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Let's see
[tex]\\ \rm\rightarrowtail Cu+AgNO_3\longrightarrow Cu(NO_3)_2+Ag[/tex]
Moles of silver :-
40.7/108=0.38mol1 mol copper produces 1 mol Ag0.38 mol Cu produces 0.38 mol Ag0.38 mol AgNO_3 produces 0.38 mol Agwhat are sediments???????????????????????
Answer:
what are sediments???????????????????????
Explanation:
Sediment is a naturally occurring material that is broken down by processes of weathering and erosion, and is subsequently transported by the action of wind, water, or ice or by the force of gravity acting on the particles.
I hope that helped you.
Answer:
a naturally occurring material that is broken down by processes of weathering and erosion.
Explanation:
Dictionaries help with definitions such as the one I've given you. :)
What is the basis for analyzing an energy transfer diagram?
The mechanical energy input and output must be equal.
Heat must always be the largest output.
The sum of all outputs must equal the input.
Electrical energy is an input but not an output.
Answer: The sum of all outputs must equal the input:
Explanation:
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Type the correct answer in the box. Round your answer to the nearest whole number.
Dylan has two cubes of iron. The larger cube has twice the mass of the smaller cube. He measures the smaller cube. Its mass is 20 grams, and its
density is 7.87 g/cm? What's the larger cube's volume?
The larger cube's volume is about cm?
Reset
Next
Answer:
Rounding volume to nearest whole number is 5cm³.
Explanation:
Given data:
Mass of smaller iron cube = 20 g
Density of cube = 7.87 g/cm³
Volume of larger cube = ?
Solution:
The mass of larger iron is twice of smaller iron cube.
It will be 40 g.
Now we will apply the density formula.
d = m/v
7.87 g/cm³ = 40 g/ v
v = 40 g/ 7.87 g/cm³
v = 5.08 cm³
Rounding answer to nearest whole number is 5cm³.
A block has dimensions 1.0 dm, 4.2 cm, and 25 mm, with a mass of 5.326 kg. Calculate the density of this block in g/cm 3 .
Answer:
1 dm equals about 10 cm
25 mm equals 2.5 cm
and then we have 4.2 cm, including a mass of 5.326 kg
How do we find the density of the block?
First, lets rewrite our formula.
d = mass divided by volume.
lets multiply 10 cm x 2.5 cm x 4.2 cm
this equals 105.
Now, lets turn 5.326 kg into what we need to divide.
1000 cm x 5.326 kg is 5326 cm
now lets do 5326 into 105
thats 50.
Explanation:
50 is the answer.
What is the correct formula for copper(ii) oxide
Answer:
CuO
Explanation:
Copper(II) oxide is a metal oxide it has the formula CuO. It has formula of copper(2+). Cupric oxide, or copper (II) oxide
2. Calculate the atomic mass of an element that has two isotopes, each with 50.00% abundance. One isotope has a mass of 63.00 amu and the other has a mass of 68.00 amu.
Answer:
The atomic mass of element is 65.5 amu.
Explanation:
Given data:
Abundance of X-63 = 50.000%
Atomic mass of X-63 = 63.00 amu
Atomic mass of X-68 = 68.00 amu
Atomic mass of element = ?
Solution:
Abundance of X-68 = 100-50 = 50%
Average atomic mass = (abundance of 1st isotope × its atomic mass) +(abundance of 2nd isotope × its atomic mass) / 100
Average atomic mass = (50×63)+(50×68) /100
Average atomic mass = 3150 + 3400 / 100
Average atomic mass = 6550 / 100
Average atomic mass = 65.5 amu.
The atomic mass of element is 65.5 amu.
name any three chemical pollutants
Answer:
Ozone (O3) Nitrogen dioxide (NO2) Carbon monoxide (CO) Sulphur dioxide (SO2)
Explanation:
Answer:
Particulate matter (PM10 and PM2. ...
Ozone (O3)
Nitrogen dioxide (NO2)
Carbon monoxide (CO)
Sulphur dioxide (SO2)
Explanation:
Particulate matter (PM10 and PM2. ...
Ozone (O3)
Nitrogen dioxide (NO2)
Carbon monoxide (CO)
Sulphur dioxide (SO2)