From a laboratory process designed to separate water into hydrogen and oxygen gas, a student collected 20.0g of Hydrogen and 158.6 g oxygen. How much water was originally involved in the process?

Answers

Answer 1

A total of 158.6gram of water were initially used in the process. Through an electrochemical process, it can be divided into hydrogen and oxygen.

How does electrochemistry work?

The area of physical chemistry known as electrochemistry studies the relationship between electrical potential difference—a measurable and quantitative phenomenon—and distinguishable chemical change, either as the result of a specific chemical change leading to a potential difference or the other way around.

Given,

Amount of Hydrogen : 20.0 g

Amount of Oxygen : 158.6g

Amount of Water used ?

Therefore,

Mass of Reactant = Mass of product

Mass of Reactant =  Mass of Hydrogen + Mass of Oxygen

Mass of Reactant   =   158.6 gram +  20 gram

Mass of Reactant (Water)   =   178.6 gram

Consequently, 178.6 grams of water were initially used in the process. Hydrogen and oxygen can be separated from it using an electrochemical process.

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Related Questions

What is true of a Lewis base?
A. A Lewis base donates electron pairs.
B. A Lewis base donates H* ions.
C. A Lewis base donates a salt in solution.
D. A Lewis base donates OH ions.

Answers

The statement that is true of a Lewis base is that a Lewis base donates electron pairs (option A).

What is a Lewis base and acid?

A Lewis base is any nucleophylic compound that can donate a pair of electrons and form a coordinate covalent bond.

On the other hand, a Lewis acid is any electrophylic compound that can accept a pair of electrons and form a coordinate covalent bond.

This means that a Lewis base can donate a pair of electrons to a Lewis acid to form a product containing a coordinate covalent bond. This product is also referred to as a Lewis adduct.

Therefore, option A is correct about Lewis base

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What are some examples of non bases

Answers

Answer:

baking soda

Explanation:

There are various uses of bases: 1: Bases are used to control the acidity which take place in your stomach. 2: Bases are used in homes, like baking soda. :)

Answer:the answer to your question is baking soda.

Joseph has hypothesized that sound travels in waves. If he were following the scientific method, what should he do next?

Answers

The following in the scientific method after the hypothesis is hypothesis testing which is carried out by experimental and or observation procedures.

What is the process of the scientific method?

The process of the scientific method involves a series of well-detailed steps to collect scientific empirical evidence, which is characterized to have data that can be tested by experimentation or observation.

The process of scientific method starts with the observation of the natural world, which leads us to raise a question that must be answered by a plausible explanation called a hypothesis. Finally, we can prove those hypotheses by using experiments to collect info and results.

Therefore, with this data, we can see that the process of the scientific method involve the application of experimentation and or observational procedures to test hypothesis and this confirm or reject their assumptions.

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the scientist most likely answer by examining this fossil?
average monthly rainfall in the area?
=r was absorbed by the roots of the plant?
en was in the atmosphere surrounding the plant?
wironment like in the area when the plant was alive? ASAP IN 5-10 minutes

Answers

The scientist most likely answer by examining this fossil is the environment like in the area when the plant was alive which is therefore denoted as option D.

What is a Fossil?

This is referred to as the remains of plants and animals which have been preserved in the earth crust.

Fossils are very important as it gives an insight into how life and humans came from and also the various ways in which the Earth and our environment has changed over the years through the presence and absence of various structures which is therefore the reason why option D was chosen as the correct choice.

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Calculate the molecular mass of sulphur if 35.5 g of sulphur dissolves in 100.0 g of CS2 to produce a solution that has a boiling point of 49.48°C.​

Answers

Since there is an exact amount of 100.0 g probably distilled there is going to be a molecular mass of a whole number, I got 64 m/g, I have

Which bond would you expect to be the most polar?
N-O
C-N
P-S
O-F
C-O

Answers

C-O

Explanation:

Thus, the largest difference of

electronegativity is between carbon and oxygen. Therefore, the C −O bond is most polar.

6.
(04.01 MC)

Sulfuric acid, H2SO4, can be neutralized by sodium hydroxide, NaOH. The unbalanced equation is:

H2SO4(aq) + NaOH(aq) → Na2SO4(aq) + H2O(l)

A student who was asked to balance the reaction wrote the following:

H2SO4(aq) + Na2OH(aq) →Na2SO4(aq) + H3O(l)

Is this correct? Explain why or why not using what you know about the law of conservation of mass and chemical changes. If necessary, provide the correct balanced equation. (5 points)

Answers

Answer:

It is not correct

Explanation:

there is no Na2OH because OH is -1 and Na is +1

there is no H30 because oxygen can only have 2 bonds with hydrogen

the balanced equation is:

H2SO4 + 2NaOH => Na2SO4 + 2H20

Larry made this picture to represent a chemical reaction:



Which of the following statements best explains the type of chemical reaction represented by Larry's picture?

a
It represents a synthesis reaction because two reactants form one product.

b
It represents a synthesis reaction because the total mass of the product is less than the mass of the reactants.

c
It represents a decomposition reaction because one reactant breaks apart and forms two products.

d
It represents a decomposition reaction because the same atoms are present in the reactants and products.

Answers

To solve such this we must know the concept of synthesis reaction. Therefore, the correct option is option A that is It represents a synthesis reaction because two reactants form one product.

What is chemical reaction?

Chemical reaction is a process in which two or more than two molecules collide in right orientation and energy to form a new chemical compound. The mass of the overall reaction should be conserved. There are so many types of chemical reaction reaction like combination reaction, double displacement reaction.

It represents a synthesis reaction because two reactants form one product. This statements best explains the type of chemical reaction represented by Larry's picture. synthesis reaction is the one where two reactant combine to form one product.

Therefore, the correct option is option A.

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The percent error for the data set is 12%, which is greater than 5%. The range of the data is 0.1, which is considered very close together.
Which sets of terms describes the accuracy and precision of the data?
A. The data is both accurate and precise.
B. The data is not accurate but is precise.
C. The data is accurate but not precise.
D. The data is neither accurate nor precise.

Answers

The percent error of the result is very high. Which means the accuracy of the data is very low. But the range of values are close to 0.1. Thus, the data is precise but not accurate.

What is accuracy?

Accuracy of a result is its closeness of the calculated or experimental value to the true value or accepted value. Thus, it tells that, how much the data can be taken to be true.

Precision is the closeness between the results of the same experiment. An experiment if  done in several trails, where the result of each time are closer then it is said to be precise.

The given results has 12% error thus, it is far from the true value indicates that the data is not accurate. But the data points comes in a close range of values. Thus. the data is precise.

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If 45.0 mL of a 6.0 M HCI solution are dilute with pure water to a volume of 1.0 L , what is the concentration of the resulting solution?

Answers

Answer: 0.27 M

Explanation:

c1V1=c2V2

c1=6.0 M;V1=45.0 mL

c2=?;V2=1.0 L=1000 mL

c2=(c1V1)/V2

c2=((6.0)(45.0))/1000

c2=0.27 M

- Carver hoped that farmers would plant
Although Carver had many talents,
crops.
was his specialty.

Answers

Carver was a peanut farmer

When 1600 joules of heat is added to a sample of solid copper (Cu), the temperature rises from 15.0 C to 30.0 C. the specific heat of solid copper is 0.385, how many grams of copper are in the sample.

Answers

Taking into account the definition of sensible heat, the mass of copper in the sample is 277.06 grams.

Definition of sensible heat

When heat added or removed from a substance causes a temperature change in it without affecting its molecular structure (physical state), it is called sensible heat.

The expression that allows to calculate heat exchanges is:

Q = c× m× ΔT

where:

Q is the heat exchanged by a body of mass m.c is the specific heat substance.ΔT is the temperature variation.

Mass of copper in the sample

In this case, you know:

Q= 1600 Jc= 0.385 J/gCm= ?ΔT= Tfinal - Tinitial= 30 C - 15 C= 15 C

Replacing in the definition of sensible heat:

1600 J = 0.385 J/gC× m× 15 C

Solving:

1600 J = 5.775 J/g× m

1600 J÷ 5.775 J/g= m

277.06 g= m

Finally, the mass of copper in this case is 277.06 grams.

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Nitrogen and hydrogen combine at a high temperature, in the presence of a catalyst, to produce ammonia.

N2(g)+3H2(g)⟶2NH3(g)

Assume 0.290 mol N2 and 0.954 mol H2 are present initially.

After complete reaction, how many moles of ammonia are produced?

Answers

Answer:

17 reactions

Explanation:

What solid substances are found in rocks that make up the Earth's crust?
A. Concrete
B. Plastics
C. Minerals
D. Miners

Answers

Answer:

minerals

Explanation:

its litteraly non of the others

The solubility product for tin II hydroxide (Sn(OH)2) is Ksp = 5.5 x 10^27
For which of the following solutions will the molar solubility of Sn(OH)2 be the largest?

a) A pH = 4.00 buffer solution
b) A pH = 6.00 buffer solution
c) A pH = 7.00 buffer solution
d) A pH = 8.00 buffer solution
e) A pH = 10.00 buffer solution

Answers

Answer:

Answer: e) A pH = 10.00 buffer solution

How would you do this??

Answers

Explanation:

A lot of the names you're just going to have to look up/know. CH4 is methane, which you would just have to know.

As for the molar mass, for each compound you have to add up the masses of each atom. Using CH4 as an example, you would have to add the mass of the carbon atom with the 4 hydrogen atoms. Using a periodic table you can see that the mass of carbon is about 12.0107 g and the mass of each hydrogen atom is about 1.008 g.

12.0107 + (4 x 1.008) = 16.0427 g

Just be careful with compounds such as Ca3(PO4)2, because there are 2 phosphorous atoms and 8 oxygen atoms.

For percent composition you have to find how much each element within the compound makes up the compound's mass. Since you will have already calculated the molar mass, you can add up the mass of a particular element within a compound and divide it by the compound's molar mass. Then multiply by 100 to get the percent.

For CH4,

Carbon:

(12.0107/16.0427) x 100 = 74.87 %

Hydrogen:

(4 x 1.008/16.0427) x 100 = 25.13 %

A 50.0 g sample of an unknown
compound contains 14.19 g Na,

19.76 g O, and 16.05 g Cr. What is

the percent composition of O in the

compound?


[?]% O


Round your answer to the hundredths place.

Answers

Taking into account the definition of percent composition, the percent composition of O in this sample is 39.52%.

Definition of percent composition

The percent composition is a measure of the amount of mass that an element occupies in a compound and indicates the percentage by mass of each element that is part of a compound.

The percent composition is calculated as the mass of the solute divided by the mass of the solution, the result of which is multiplied by 100 to give a percentage:

percent composition= (mass of solute÷ mass of solution)× 100%

Percent composition of O

In this case, you know that a 50 g sample contains 14.19 g of Na, 19.76 g of O, and 16.05 g of Cr.

Dividing the amount of mass of O present by the mass of the sample and multiplying it by 100, the percent composition of O can be obtained:

Percent composition of O= (19.76 g÷ 50 g)× 100%

Percent composition of O= 39.52%

Finally, the percent composition of O in the compound is 39.52%.

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Which of the following would have the most momentum?
A. A tennis ball traveling a 10 meters/second
B. A tennis ball traveling at 5 meters/second.
C. A tennis ball traveling at 3 meters/ second
D. A tennis ball sitting on the ground.

Answers

Answer:

A tennis ball traveling at 10 meters per second.

Explanation:

This is due to the fact that there is more speed- so more moentum.

(f) Which structure represents the arrangement of atoms in pure copper? A B C D Tick one box. A B C D​

Answers

Structure A represents the arrangement of atoms in pure copper because  copper is a solid and only made of one type of atom.

What is pure copper described as?

The chemical element copper has the atomic number 29 and the symbol Cu. Copper, a transition metal, is a solid at ambient temperature.

Pure copper has a low hardness, is exceedingly ductile, and is malleable. For electrical applications, a number of reasonably pure Cu grades are produced, with small variances in deoxidation.

Solid copper is defined as a face-centered-cubic (fcc) arrangement of copper atoms.

Thus, structure A correctly represents the arrangement of atoms in pure copper.

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Which of the following explains why saltwater is considered a mixture?
It is composed of two or more substances and has new chemical properties.
O It is composed of one element
O It is composed of two or more substances that retain their own chemical properties.
O
It is composed of one compound

Answers

Answer:

the answer is the option A

5. Practice: Turn off Show electron dot diagram. Use the Gizmo to create a neutral atom of
each of the following elements. Draw an electron dot diagram for each. When you are
finished, turn on Show electron dot diagram and check your answers.
H
He
Li
Be
B
C
N
O
F
Me
Na
Mg
Al
Si

Answers

Answer:  You would put one dot for each valence electron the element has so Hydrogen would be 1 He:2 Li:1 Be:2  B:3 C:4 N:5 O:6 F:7 Ne:10

Na:1 Mg:2 Al:3 Si:4

Explanation:

This is also called the lewis structure you will draw the dots around the letter. 2 on each side and there are 4 sides per letter

Lewis diagram, or Lewis structure, is a diagram that employs dots to represent the valence electrons of such an atom. Hydrogen has 1 valence electron.

What is electron dot diagram?

A Lewis electron dot diagram, also known as an electron dot diagram, Lewis diagram, or Lewis structure, is a diagram that employs dots to represent the valence electrons of such an atom. The amount of dots corresponds to the atom's valence electron count.

Chemical bonds are virtually often created by interactions between atoms' valence electrons. A straightforward technique to depict those valence electrons might be helpful to improve our comprehension of how they interact.

Element                         number of electron

   H                                    1

   He                                   2

  Li                                     1

  Be                                   2

Therefore, in above given way number of valence electron can be shown.              

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Need help please …..

Answers

Answer:

A( is the the first one B( is the third

what is the pH of a 0.0250 M solution of an acid HY that is 0.038% dissociated?

Answers

0.025 M HCl solution has a pH of −log(0. 025)=1. 60.

How do you calculate pH from dissociation?

The acid dissociation constant (Ka) must be used to determine [H+] even if the pH equation remains the same (pH = -log[H+]). The concentration of hydrogen ions can be calculated using one of two approaches. The quadratic equation is one. The other makes the assumption that the weak acid hardly separates from water and approximates the pH.

The pH of a 0.025 M HCl solution is 1.60 log (0. 025).

Acid dissociation percentage is calculated by multiplying [H+] [HA] by 100.

In most cases, the dissociation constant is computed by dividing the concentration of the solution by the concentration of each dissociated ion. For an all-purpose acid-base reaction, such as: HA + H 2 O H 3 O + + A

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How does Musculo-Skeletal System and Integumentary System work together in the human body

Answers

The musculoskeletal and integumentary systems work together in the human body to ensure that the body is protected from injury and cold.

The musculoskeletal system and integumentary system also work together in the human body to ensure that the weight of the body is effectively supported and to ensure movement of the body.

What are the Musculo-Skeletal System and Integumentary System of the body?

The musculoskeletal system of the body refers to the systems of the organs and tissues that give shape and structure to the body as well as ensure the movement of body parts.

The musculoskeletal system includes all the bones and muscles of the body.

The Integumentary System of the body is the system of organs, tissues, and cells that provides a covering to the body acting as a physical barrier that protects the body from infection, injury, and sunlight.

The Integumentary System of the body includes the skin, nails, hair, and the glands and nerves on your skin.

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A polyatomic ion is several ________ bonded together with ___________ ionic charge.

Answers

Answer:

A polyatomic ion, also known as a molecular ion, is a covalent bonded set of two or more atoms, or of a metal complex, that can be considered to behave as a single unit and that has a net charge that is not zero. They form a stable grouping which carries a charge (positive or negative). The group of atoms as a whole acts as a charged species in forming an ionic compound with an oppositely charged ion.

Equilibrium is established for the reaction 2 X(s) + Y(g) ⇌ 2 Z(g) at 500K, the Kc value is 100.
Determine the concentration of Z in equilibrium with o.2 mol of X and 0.50 M of Y at 500K

Answers

Answer:

Equilibrium is established for the reaction 2 X(s) + Y(g) ⇌ 2 Z(g) at 500K, the Kc value is 100.

Determine the concentration of Z in equilibrium with o.2 mol of X and 0.50 M of Y at 500K

answer

At equilibrium, the concentrations of X and Y will remain constant, so we can use the Kc expression to solve for the concentration of Z:

Kc = [Z]^2 / [X]^2

[Z]^2 = Kc * [X]^2

[Z]^2 = 100 * (0.2)^2

[Z] = √(100 * 0.04)

[Z] = 0.2 M

How many grams of Ag₂S₂O₃ from when 125.0g AgBr reacts completely according to the reaction below?
2AgBr + Na₂S₂O₃ → Ag₂S₂O₃ + 2NaBr
Ag₂S₂O₃ : 327.74 g / mol
AgBr : 187.70 g / mol
______g? Ag₂S₂O₃

Answers

Since, 2AgBr + Na₂S₂O₃ → Ag₂S₂O₃ + 2NaBr

Ag₂S₂O₃= 327.74 g / mol

AgBr= 187.70 g / mol

Hence, amount of Ag₂S₂O₃ formed in this chemical reaction is 200g.

What is a chemical reaction?

Chemical reaction, a process in which one or more substances, the reactants, are transformed into one or more different substances, the products. Substances are either chemical elements or compounds. A chemical reaction rearranges the basic atoms of the reactants to form different substances as products.Chemical reactions must be distinguished from physical changes. Physical changes include changes of state, such as ice melting to water and water evaporating to steam. If a physical change occurs, the physical properties of the substance will change, but its chemical identity will remain the same. Regardless of its physical state, water (H2O) is the same compound, with each molecule consisting of two hydrogen atoms and one oxygen atom. However, when water, such as ice, liquid, or steam, meets metallic sodium (Na), the atoms rearrange to give the new substances molecular hydrogen (H2) and sodium hydroxide (NaOH).

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There is a current of 0.45 A through a lightbulb in a 120 V circuit. What is the resistance of this lightbulb?

Answers

The resistance of the light bulb is 266.7Ω

What is resistance?

When an electric current flows through a bulb or any conductor, the conductor offers some obstruction to the current and this obstruction is known as electrical resistance and is denoted by R. Every material has an electrical resistance and this is the reason why conductors give out heat when current passes through it. The unit of electrical resistance is ohms.

According to Ohm’s law, there is a relation between the current flowing through a conductor and the potential difference across it. It is given by,

V ∝ I V = IR

Where,

V is the potential difference measured across the conductor (in volts)

I is the current through the conductor (in amperes)

R is the constant of proportionality called resistance (in ohms)

Therefore, R = V/I

To find the Resistance;

R = V/I

where V = 120V

I = 0.45A

R = 120/0.45

R = 266.7Ω

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The activation energy for a particular reaction is 102 kJ/mol. If the rate constant is 1.35 × 10⁻⁴ s⁻¹ at 306 K, what is the rate constant at 273 K?

Answers

To solve this type of question we must know the expression for rate law for first order kinetics. Therefore, the rate constant at 273 K is 8.11 x 10⁻⁷s⁻¹.

What is the expression for rate law for first order kinetics?

There are two kinds of rate law in chemical kinetics one is differential rate law and other is integrated rate law.

ln(k₁/k₂ )=-Ea /R(1/T₁-1/T₂)

Ea=102 kJ/mol

k₁=1.35 × 10⁻⁴ s⁻¹

T₁=306 K

k₂=?

T₂= 273 K

R=8.314J/kmol

substituting all the given values in the above equation, we get

ln(1.35 × 10⁻⁴ /k₂ )=-1.35 × 10⁻⁴ /8.314(1/306-1/273)

K[tex]_2[/tex]=8.11 x 10⁻⁷s⁻¹

Therefore, the rate constant at 273 K is 8.11 x 10⁻⁷s⁻¹.

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Write a balanced chemical equation for the standard formation reaction of solid vanadium(V) oxide?

Answers

A balanced chemical equation for the standard formation reaction of solid vanadium ( V ) oxide is 4VO₂ + O₂ ⇒ 2V₂O₅.

What is vanadium oxide ?

The inorganic chemical with the formula V2O5 is called vanadium(V) oxide. Commonly referred to as vanadium pentoxide, it is a deep orange solid that is brown or yellow when freshly precipitated from aqueous solution. It is both an oxidizing agent and an amphoteric oxide due to its high oxidation state.

A lot of industrial chemical reactions use vanadium oxide as a catalyst. The following applications also employ it: in the production of laser crystals and other optical applications. in the use of nanowire and nanofiber.

Thus, A balanced chemical equation for the standard formation reaction of solid vanadium ( V ) oxide is 4VO₂ + O₂ ⇒ 2V₂O₅.

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