Consider the following reaction. 2Fe2O3 --> 4Fe + 3O2 deltaH = +824.2KJ The formation of 42.0 g of O2 results in? 1) the absorption of 361 kJ of heat. 2) the absorption of 11500 kJ of heat. 3) the absorption of 1080 kJ of heat.

Answers

Answer 1
If deltaH is positive, that means the reaction took heat from its environment (endothermic reaction).
   The molar mass of O2 is 32 g/mol.
 Therefore, 42g of O2 is equal to 1.3 moles O2.
   The equation assumes 3 moles of O2. That means, only 1.3/3 = 43% of the delta H in the equation was formed.
   824.2 kJ x 43% = 354 kJ. The closest answer is 1) the absorption of 361 kJ of heat.
Answer 2

The formation of oxygen in the reaction, the absorption of 361 kJ of heat takes place.

The heat of formation of oxygen will be

[tex]\rm \Delta H[/tex] is +824.2 kJ.

The positive sign of H denotes that the reaction accepts energy from the surroundings. It is an endothermic reaction.

In the reaction the % formation of Oxygen is :

Total product formed = 7 moles

Oxygen formed = 3 moles

% Oxygen formed = [tex]\rm \frac{3}{7}\;\times\;100[/tex]

% oxygen formed  = 42.85 %

The total enthalpy for the formation of product is +824.2 kJ.

The enthalpy for the formation of 42.85 % Oxygen = +824.2 [tex]\times[/tex] 42.85 / 100 kJ.

The enthalpy of the formation of oxygen in the reaction will be 353.22 kJ.

The closest is 361 kJ.

So, for the formation of oxygen in the reaction, the absorption of 361 kJ of heat takes place.

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Related Questions

The partial pressure of carbon dioxide in systemic arterial blood is __________. the partial pressure of carbon dioxide in systemic arterial blood is __________. 100 mm hg 40 mm hg 104 mm hg 45 mm hg

Answers

In the systemic arteries, the partial pressure of carbon dioxide is  40 mm Hg.  Partial pressure of a gas is the contribution of one gas to the total pressure exerted by all gases. Partial pressure of carbon dioxide in arterial blood is the portion of total blood gas pressure that is exerted by carbon dioxide. It decreases during heavy exercise, during rapid breathing, or in association with severe diarrhea, uncontrolled diabetes or the diseases of the kidney. It increases with chest injuries and respiratory disorders. In the systemic arteries, the partial pressure of  oxygen is 100 mm Hg.

The partial pressure of carbon dioxide (PCO2) in systemic arterial blood is approximately 40 mm Hg.

The partial pressure of a gas in a mixture, like blood, is a measure of the pressure that gas exerts independently, assuming ideal behavior. In the context of blood gases, PCO2 is a crucial parameter reflecting the concentration of dissolved carbon dioxide in the bloodstream.

Normal systemic arterial blood PCO2 levels typically range from 35 to 45 mm Hg. This range is maintained within a very narrow margin as part of the body's acid-base balance, regulated by the respiratory system and the kidneys.

A PCO2 value significantly higher than 45 mm Hg can indicate respiratory acidosis, a condition where the blood becomes too acidic due to excess carbon dioxide. On the other hand, a PCO2 value below 35 mm Hg may indicate respiratory alkalosis, where the blood becomes too alkaline due to insufficient carbon dioxide.

Therefore, a PCO2 of 100 mm Hg, 104 mm Hg, or 45 mm Hg does not represent the typical PCO2 in systemic arterial blood and would suggest an abnormal condition. A PCO2 of 40 mm Hg is within the normal range for systemic arterial blood PCO2.

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#1: A material has a density of 8.9 g/cm^3. You have six cubic centimeters of the substance. What is the material’s mass in grams?

A. 3.0 g

b. 5.9 g

C. 27 g

D. 53 g
**Idk i think it is either C. 27 g or D. 53 g :/

Answers

The density of a material = mass/ volume From the question, volume = 6 cm^3. Since the density = 8.9 g/cm^3 We have that 8.9 = mass/ 6 So mass = 8.9 * 6 = 53.4 So it follows that our mass = 53.4g. Hence option D which is 53g.

Which of the following represents a chemical change. A water to boiled
B Paper is torn
C Glass is shattered
D Wood is burned

Answers

Hello,

Here is your answer:

The proper answer to this question is option D "wood is burned". Its a chemical change because its changing forms wood to ash.

Your answer is D.

If you need anymore help feel free to ask me!

Hope this helps!

to answer your second question, it is D

If 36 grams of aluminum react with an excess of oxygen, as shown in the balanced chemical equation below, how many grams of aluminum oxide can be formed? (1 point)

4Al + 3O2yields 2Al2O3

68 grams
24 grams
272 grams
18 grams

Answers

molar mass of Al = 26.98
molar mass of Al2O3 = 101.96
36 / 26.98 = 1.3343 moles Al 
set up a proportion : 1.3343 / 4 = x / 2 (let x = moles of Al2O3) 
x = 0.66716 moles of Al2O3
0.66716 * 101.96 = 69.024 g of Al2O3 

A 10.0-L rigid container holds 3.00 mol H2 gas at a pressure of 4.50 atm. What is the temperature of the gas?

Answers

We can approach this problem using the ideal gas law which is as follows:

PV = nRT

P = pressure
V = volume
n = number of moles
R = gas constant, 0.08206 Latm/Kmol
T = temperature

We are asked to solve for temperature and can rearrange the equation to solve for T:

PV = nRT
T = PV/nR

Now we simply plug in the data to solve for T:

T = (4.50 atm)(10.0 L)/(3.00 mol)(0.08206 Latm/Kmol)
T = 183 K

The temperature of the gas is 183 K.

Answer. A. 183

B. 142

C. 0.03

D.11.3

E.24.5

Explanation:

Pls hurry!!
If the percent (mass/mass) for a solute is 4% and the mass of the solution is 200 g, what is the mass of solute in solution?
8.0 g
50 g
80 g
800 g

Answers

Percent Mass of solute is 4% ==> 4g of solute is present in 100g of the solution. 

given mass of solution is 200g therefore mass of solute 
= 4% of 200g 
= 8g 
therefore mass of solute = 8g 

Answer : The correct option is, (a) 8.0 g

Solution : Given,

Percent of solute = 4 %

Mass of solution = 200 g

Mass by mass percent (m/m)% : It is defined as the mass of solute present in the mass of solution.

Formula used :

[tex](m/m)\%=\frac{\text{Mass of solute}}{\text{Mass of solution}}\times 100[/tex]

Now put all the given values in this formula, we get the mass of solute.

[tex]4\%=\frac{\text{Mass of solute}}{200g}\times 100[/tex]

[tex]\text{Mass of solute}=8.0g[/tex]

Therefore, the mass of solute in solution is, 8.0 g

#1: Which of the following is an exothermic reaction?

A. dissolving ammonium nitrate in water to cool the water

B. condensation

C. melting ice

D. dissolving sugar in water


**my answer; C

is that right? @aaronq :)

Answers

An exothermic reaction is one in which heat is released from the reagents into the ambient environment. Perhaps somewhat counterintuitively, condensation is in fact an example of such a reaction. During the process of the gas-to-liquid phase change, water goes from a higher-energy to lower-energy state of matter, and, as such, releases heat into the environment.

PLEASE HELP ASAP
In two or more complete sentences describe how atomic radius changes as you move down a group in the periodic table and why.

Answers

Answer:

When we move across the period from left to right then there is decrease in atomic radius.

This is due to increase in number of protons and electrons across a period. Since electrons are added in same energy level, therefore, they get pulled closer to the nucleus because of more number of protons which carry a positive charge.

As a result, there is shrinkage in size from left to right across the period.

Hope this helped!

Explanation:

The atomic radius increase as we move down the group in the periodic table because of the addition of a new principal shell.

What is the atomic radius?

The atomic radius of an atom can be described as the shortest distance between the nuclei of the atom and the valence shell of the atom. An atomic radius is also specified as half the distance between two adjacent atoms of the same element directly bonded in a molecule.

In general, the atomic radius of an atom increases when we move down a group on the modern periodic table. In groups in the periodic table, the addition of a new principle shell as we move down. Therefore the distance between the nucleus and the outermost shell increases and the electronegativity decreases and the atomic radius increases.

In periods in the periodic table, the electrons are in the same valence shell therefore the atomic number of elements increases within the same period. While moving from left to right, the effective nuclear charge increases.

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Hi, I can't seem to answer the letter b.--> An empty vial weighs 55.32 g. (a) If the vial weighs 185.56 g when filled with liquid mercury (d 13.53 g/cm3), what is its volume? (b) How much would the vial weigh if it were filled with water (d 0.997 g/cm3 at 25°C)?,

Answers

Subtract the mass when full from the mass when empty.
185.56 - 55.32 = 130.26 g. 
Divide by the density of liquid mercury to find the volume.
130.26 g / 13.53g/cm^3 = 9.62601626 cm, the volume of the vial.

If water was used instead of mercury, the fluid mass would be
9.62601626 cm * .997 g/cm^3 = 9.597 g

Adding this to the empty vial mass of 55.32 gives a final mass of 64.916 g.

The following chemical equation is not balanced: C3H8 + O2 CO2 + H2O When this chemical equation is correctly balanced, what is the coefficient of the carbon dioxide molecule?

Answers

C3H8 +5O2 -> 3CO2+4H2O

3 would be the answer to your question...

What is the empirical formula of a compound composed of 32.9g of potassium and 6.73 g of oxygen

Answers

The  empirical   formula   is  calculated  as   follows
   step 1 ;  calculate   the   moles  of   each  element

K =  32.9 g/39  g/mol  (molar  mass of   potassium)   =  0.84  moles
 
O =  6.73 g  /16  g/mol  (  molar   mass   of  oxygen)  =  0.42  moles

step 2 ;  calculate  the  mole  ratio     by  dividing  by  smallest  number  of  mole
K=  0.84 /0.42=2 
O=   0.42/0.42=  1

therefore  the  empirical    formula  =  K2O

When a 10 mL graduated cylinder is filled to the 10 mL mark, the mass of the water was measured to be 9.925 g. If the density of water is taken to be 0.9975 g/mL, what is the percent error for the 10 mL of water,

Answers

measured volume = 10 ml 
mass = 9.925 g 
density = 0.9975 g/ml
density = [tex] \frac{mass}{volume} [/tex] 
so actual volume = [tex] \frac{mass}{density} [/tex] = [tex] \frac{9.925}{0.9975} [/tex] = 9.95 mL
Percentage Error = [tex] \frac{measured volume - Actual volume}{actual volume} [/tex] x 100 
= [tex] \frac{10 - 9.95}{9.95} [/tex] x 100 = 0.5 % error
Final answer:

The percent error for the 10 mL of water, given a measured mass of 9.925 g and a density of 0.9975 g/mL, is approximately 0.501%.

Explanation:

To calculate the percent error for the 10 mL of water given the measured mass and the density of water, we can use the formula for percent error:

Percent Error = | (Experimental Value - Theoretical Value) / Theoretical Value | × 100%

The theoretical mass of 10 mL of water using the density 0.9975 g/mL is calculated as follows:

Theoretical Mass = Volume × Density = 10 mL × 0.9975 g/mL = 9.975 g

The experimental mass measured is 9.925 g. Now, applying the percent error formula:

Percent Error = | (9.925 g - 9.975 g) / 9.975 g | × 100% = |(-0.05 g) / 9.975 g| × 100% ≈ 0.501%

Therefore, the percent error for the measurement of 10 mL of water is approximately 0.501%.

a mixture of 10.0 g of Ne and 10.0 g AR have a total pressure of 1.6 atm. what is the partial pressure of Ne?
Actually I know the answer but I didn't know how they get 2/3

Answers

The partial pressure contributed to the overall pressure is proportional to the number of moles of gas particles. Both Neon and Argon are noble gases so there's just 1 atom per molecule. So let's determine how many moles of each we have:
 Atomic weight neon = 20.1797
 Atomic weight argon = 39.948

   Moles neon = 10.0 g / 20.1797 g/mol = 0.495547506 mol
 Moles argon = 10.0 g / 39.948 g/mol = 0.250325423 mol

   So there's a total of 0.495547506 + 0.250325423 = 0.745872929 moles of gas particles. And for neon, it contributes 0.495547506/0.745872929 = 0.664385965 = 66.4385965% of them, so it contributes 66.4385965% of the total pressure. Which is 66.4385965% * 1.6 atm = 1.063017544 atm.

Rounding to 3 significant figures gives 1.06 atm, or 66.4% of the total pressure.

The partial pressure of Ne is [tex]\boxed{1.063{\text{ atm}}}[/tex].

Further Explanation:

Dalton’s law:

This law states that partial pressure of any gas is calculated by the multiplication of mole fraction and the total pressure of gas mixture.

The expression for partial pressure of a particular gas is,

[tex]{P_{{\text{gas}}}} = {X_{{\text{gas}}}} \cdot {P_{{\text{total}}}}[/tex]                                                                         …… (1)

Where,

[tex]{P_{\text{gas}[/tex] is the partial pressure of the gas.

[tex]{P_{{\text{total}}[/tex] is the total pressure of the mixture.

[tex]{X_{{\text{gas}}}[/tex] is the mole fraction of gas.

The formula to calculate moles of component is as follows:

[tex]{\text{Moles of component}} = \dfrac{{{\text{Mass of component}}}}{{{\text{Molar mass of component}}}}[/tex]                                   …… (2)

Substitute 10.0 g for mass of component and 20.179 g/mol for molar mass of component in equation (2) to calculate moles of Ne.

 [tex]\begin{aligned}{\text{Moles of Ne}} &= \frac{{{\text{10}}{\text{.0 g}}}}{{{\text{20}}{\text{.179 g/mol}}}} \\ &= 0.4956{\text{ mol}} \\\end{aligned}[/tex]

Substitute 10.0 g for mass of component and 39.948 g/mol for molar mass of component in equation (2) to calculate moles of Ar.

 [tex]\begin{aligned}{\text{Moles of Ar}} &= \frac{{{\text{10}}{\text{.0 g}}}}{{{\text{39}}{\text{.948 g/mol}}}} \\&= 0.2503{\text{ mol}} \\ \end{aligned}[/tex]

Total number of moles can be calculated as follows:

[tex]\begin{aligned}{\text{Total number of moles}} &= \left( {0.4956 + 0.2503} \right){\text{ mol}} \\ &= 0.7459{\text{ mol}} \\\end{aligned}[/tex]

The formula to calculate mole fraction of Ne is as follows:

[tex]{\text{Mole fraction of Ne}} = \dfrac{{{\text{Moles of Ne}}}}{{{\text{Total number of moles}}}}[/tex]                                    …… (3)

Substitute 0.4956 mol for moles of Ne and 0.7459 mol for total number of moles in equation (3).

[tex]\begin{aligned}{\text{Mole fraction of Ne}} &= \frac{{{\text{0}}{\text{.4956 mol}}}}{{{\text{0}}{\text{.7459 mol}}}} \\&= 0.6644 \\\end{aligned}[/tex]  

Substitute 0.6644 for [tex]{X_{{\text{gas}}}}[/tex] and 1.6 atm for [tex]{P_{{\text{total}}}}[/tex] in equation (1) to calculate partial pressure of Ne.

[tex]\begin{aligned}{P_{{\text{Ne}}}} &= \left( {0.6644} \right)\left( {1.6{\text{ atm}}} \right) \\&= 1.063{\text{ atm}} \\\end{aligned}[/tex]  

Learn more:

Calculate the moles of chlorine in 8 moles of carbon tetrachloride: https://brainly.com/question/3064603 ]Which law states the direct relationship between volume and absolute temperature at constant pressure? https://brainly.com/question/1403211

Answer details:

Grade: Middle School

Subject: Chemistry

Chapter: Gases and the kinetic-molecular theory  

Keywords: partial pressure, mole fraction, Ne, Ar, moles, molar mass, mass, 1.063 atm, 1.6 atm, 0.6644, mole fraction of Ne.

A manganese atom is pictured below.



How many electrons would be free floating and able to form a metallic bond?

1
2
15
24

Answers

Manganese   has  2 (two) electron  that   would  free  floating   and   able  to  form  a  metallic  bond.

  The    electronic  configuration  of  manganese  is  (Ar)  3d5 4s2.  The   two   electron  in  4s  orbital  are  the  valence    electron  which  can  freely  move  from  one  place  to  another.



The correct answer is 2

How many molecules are in 2.10 mol CO ?

A.) 2.53 x 10^24
B.) 3.49 x 10^-24
C.) 3.79 x 10^24
D.) 1.26 x 10^24

Answers

d) 1.26 x 10^24

Hope this helped!

The number of molecules present in 2.10 moles of CO₂ is 1.264×10²⁴ molecules. Therefore, option D is correct.

What do you mean by mole ?

The mole is the amount of substance in a system that contains as many elementary entities as there are atoms in 0.012 kilogram of carbon 12; its symbol is "mol".

In the International System of Units, the mole (symbol mol) is the unit of substance amount (SI). The amount of substance is a measurement of how many elementary entities of a given substance are present in an object.

From Avogadro's hypothesis as follows;

1 mole of any substance = 6.023×10²³ molecules.

This implies that:

1 mole of CO₂ = 6.023×10²³ molecules

With the above information, we can obtain the number of molecules in 2.10 moles of CO₂. This can be obtained as given below:

1 mole of CO₂ = 6.023×10²³ molecules

Then,

2.10 moles of CO₂ = 2.10 × 6.02×10²³

2.10 moles of CO₂ = 1.264×10²⁴ molecules

Thus, the number of molecules present in 2.10 moles of CO₂ is 1.264×10²⁴ molecules., option D is correct.

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Which of the following separation methods is used to separate plant pigments?
(Points : 3)
chromatography

simple distillation

fractional distillation

filtration

Answers

Chromatography is the technique used to separate mixtures into the components that make up those mixtures. In chromatography the different pigments are separated into bands of pigment through their differences in intermolecular forces.

Answer: chromatography

Explanation:

Chromatography : It is a type of separation process in which the liquid or gas is separated into components at different rate. The principle of chromatography is that the substance of molecule are distributed between the liquid phases. It involves a stationary and a mobile phase.  Hence,chromatography is a laboratory technique that is used to  separate plant pigments.

Distillation : It is a type of separation process in which the mixture of liquid separated or evaporated at different temperatures.

Fractional distillation is separation of a liquid mixture into fractions which differ in boiling points by means of distillation by use of a fractionating column.

Filtration : It is a type of mechanical separation process in which the solid is separated from the liquid through the filter paper.

Ozone, O3(g), is a form of elemental oxygen produced during electrical discharge. Is ΔH∘f for O3(g) necessarily zero? Yes or no question?

Answers

The answer for your question is No. This is because in given conditions, it is not the most stable form of oxygen's element. It will not equate into zero because there will be charge remained after balancing the equation. 

Answer: ΔH°f is not zero

Explanation:

the change in enthalpy formation is zero when elements are pure.when they are zero it is mainly  because they are most basic,where you cannot form an element with an element.

Describe the solid state according to the kinetic molecular theory

Answers

 the kinetic molecular theory states that all matter is made up tiny constantly moving particles. in a gas they are spread out very far from each other, a liquid is closer together and a solid is packed tightly. when these materials are heated the particles begin to move faster making more friction which causes changes in state, such is call the heat if fusion and vaporization.

The kinetic molecular theory describes the solid state as composed of tightly packed particles that vibrate about fixed positions and are held together by strong intermolecular forces. This leads to solids having a defined shape and volume, and being less compressible compared to liquids and gases.

Solid State According to the Kinetic Molecular Theory

The kinetic molecular theory is a framework used to describe the behavior of matter in different states - solid, liquid, and gas. According to this theory, the solid state of matter is characterized by particles that are tightly packed together, often in a regular pattern. These particles have very little movement, primarily vibrating about fixed positions.

In the context of the kinetic molecular theory, intermolecular attractions are significant in the solid state, holding the particles closely to one another. This close packing and the limited movement of particles correspond to the low kinetic energy compared to gases. These properties explain why solids have a definite shape and volume, and why they are not easily compressible.

Focusing on the particles' behavior in solids, we understand that the restricted motion due to strong intermolecular forces results in the characteristic rigidity and structural stability of the solid state. Although the particles are in motion, it is minimal and does not allow for the particles to move past each other, unlike in liquids or gases.

6.5 moles AlCl3 reacts with 57.0g of NaOH. how many grams of Al(OH)3 will be produced

Answers

the equation for the reaction between NaOH and AlCl₃ is as follows;
3NaOH + AlCl₃ ---> 3NaCl + Al(OH)₃
the stoichiometry of NaOH : AlCl₃ is 3:1
3 moles of NaOH reacts with 1 mol of AlCl₃ to produce 1 mol of Al(OH)₃
the number of AlCl₃ moles reacted - 6.5 mol
molar mass of NaOH -(23 +16 +1) = 40 g/mol
the number of NaOH moles reacted = 57.0 g / 40 g/mol
 NaOH moles = 1.425 mol
either NaOH or AlCl₃ is in excess and other is the limiting reactant.
limiting reactant is the reactant whose number of moles are fully consumed during the reaction. the reactant that is in excess will have leftover moles that are remaining after the reaction.
If AlCl₃ is the limiting reactant, number of NaOH moles would be thrice the amount of AlCl₃ present,
then number of NaOH moles that should be present - 6.5 * 3 = 19.5 mol
however there are only 1.425 mol of NaOH present, therefore AlCl₃ is in excess.
Then NaOH is the limiting reactant,
the amount of products formed depends on the amount of the limiting reactant present.
stoichiometry of NaOH : Al(OH)₃ is 3:1
the number of Al(OH)₃ moles produced = number of NaOH moles reacted / 3
 number of Al(OH)₃ moles are - 1.425 mol /3  = 0.475 mol
molar mass of Al(OH)₃ = (27 +3*16 + 3*1) = 78 g/mol
mass of Al(OH)₃ produced = 78 g/mol * 0.475 mol = 37.05 g

In which case are the two atoms different isotopes of the same element?

Answers

Well the isotopes are the actual mass of that particular type of element so the most common examples would radioactive considering they are always decaying but there's also carbon-12, carbon-14, and carbon-15

A liquid that evaporates at a slow rate exhibits __________.

strong intermolecular forces

weak intermolecular forces

no intermolecular forces

a low volatility

Answers

strong internolecurar forces (A) hope it helps

Substances with weaker intermolecular forces evaporate faster due to higher vapor pressure and volatility.

Substances with weaker intermolecular forces evaporate faster than substances with stronger intermolecular forces.

Weak intermolecular forces lead to a higher vapor pressure and increased volatility in substances, causing them to evaporate at a faster rate.

Why does Tom Zambrano think that renewable energy science is a good choice for a career?

Answers

Answer:

There will many opportunities in the field of renewable energy science and engineering. It is an exciting field, with a lot of variety and room for new ideas.

Explanation:

Answer:Sample Response:

There will many opportunities in the field of renewable energy science and engineering. It is an exciting field, with a lot of variety and room for new ideas.

Explanation:

What did you include in your response? Check all that apply.

opportunities

exciting field

variety

room for new ideas

Which
molecule has the same shape and hybridization as methane

Answers

Hi, the answer is CF2Cl2 :)

Answer:

cfcl2

Explanation:edg

Jose’ has a circular rug on the floor of his bedroom. If the area of the rug is 16π square feet, what is the diameter of the rug? The diameter of the rug is feet.

Answers

Answer: 8 feet

Explanation:

1) The diameter and the area of a circle are related by this formula:

Area = π (radius)^2 = π (diameter / 2) ^2 = π (diameter)^2 / 4

2) Since you know the area you can find the formula for the diameter:

(diameter)^2 = 4 * area / π

=> diamter = √ [4*area / π]

3) Replace the value of the area

area = 16π (feet)^2

=> diameter = √ [ 4 * 16 π (feet)^2 / π ] = √ 64 feet = 8 feet

Answer: diameter = 8 feet

What describes the change in oxidation states of the following reaction?

2Cl- + F2 > 2F- + Cl2

a. Cl– reduces to Cl and F oxidizes to F–.
b. Cl– oxidizes to Cl and F reduces to F–.
d. Cl is the reducing agent and F– is the oxidizing agent.

Answers

The answer is B, Cl- oxidizes to Cl and F reduces to F-.An oxidizing agent, gains electrons and is reduced in a chemical reaction. While reduction Reductio is the loss of oxygen atom from a molecule which results to gaining electrons.

How mary significant igures are in the messurement 20,500 liters?

Answers

Answer:  "3 (three) " .
_______________________________________________________
The, "2" , "0" , and "5" , are the three (3) significant figures.
_______________________________________________________

Stoichiometry
---
Use the following reaction to determine the number of liters of hydrogen that must react with 20 L of oxygen to form water vapor.
---
Equation:
---
2H2  +  O2   ->   2H2O
---

Answers

stoichiometry is the ratio of reactants to products in a balanced chemical reaction equation. 
the stoichiometry in this case of H₂ to O₂ is 2:1.
This means that 2 moles of H₂ reacts with 1 mol of O₂.
we have been asked to calculate the volume of H₂ gas.
Since both O₂ and H₂ are gases, at standard conditions its stated that molar volume of gases is 22.4 L
This means that at standard temperature and pressure, 1 mol of any gas occupies a volume of 22.4 L
first we need to calculate the number of O₂ moles reacted;
22.4 L of gas - 1 mol of O₂
1 L of gas - 1/22.4 mol/L 
then 20 L of O₂ - 1/22.4 mol/L * 20 L = 0.89 mol
stoichiometry of H₂ to O₂ is 2:1
the number of H₂ moles = 0.89*2 = 1.79 mol
1 mol occupies 22.4 L
Therefore 1.79 mol = 22.4 L/mol * 1.79 mol = 40 L
Therefore it can be seen that stoichiometry applies to volumes as well.
volume of H₂ : O₂ = 40 L : 20 L = 2:1
volume and moles both can be determined by stoichiometry.
Volume of H₂ reacted = 40 L

9.25 * 10^21 pennies if how many moles

Answers

according  to  Avogadro constant   1  mole  =  6.02  x   10^23    what  about   9.25  x10  ^21

that  is    1  mole  x   (  9.25  x10  ^21)  /  (6.02 x10^23)  =  0.0154  moles

Enriched weapons-grade uranium consists of 80% uranium-235 (235.044 amu) and 20% uranium-238 (238.051 amu). what is the average atomic mass of weapons-grade uranium, assuming the percentages are exact?

Answers

Final answer:

To find the average atomic mass of weapons-grade uranium, calculate the weighted average based on the percentages of each isotope: 80% of 235.044 amu (uranium-235) and 20% of 238.051 amu (uranium-238), yielding an average atomic mass of 235.6454 amu.

Explanation:

To calculate the average atomic mass of weapons-grade uranium, which consists of 80% uranium-235 and 20% uranium-238, you multiply the mass of each isotope by its relative percentage (expressed as a decimal) and then sum the results. The atomic mass unit (amu) for uranium-235 is 235.044 and for uranium-238 is 238.051.

The average atomic mass can be calculated as follows:

(80% of uranium-235) 80/100 × 235.044 amu = 188.0352 amu

(20% of uranium-238) 20/100 × 238.051 amu = 47.6102 amu

Add these values together: 188.0352 amu + 47.6102 amu = 235.6454 amu

Therefore, the average atomic mass of weapons-grade uranium is 235.6454 amu.

if an object 18 millimeters high is placed 12 millimeters from a diverging lens and the image is formed 4 mm in front of the lens what is the height of the image

Answers

I think the answer is 7mm but I'm not sure.

Have a great day!

The answer is 6mm

You're welcome!

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