calculate the volume of hydrogen produced at s.t.p when 25g and zinc are added to excess dilute hydrochloric acid at 31 degrees and 778 mm Hg pressure ( H= 1 , Zn = 65 , cl = 35.5 , volume of gas at stop = 22.4 dm cube​

Answers

Answer 1

Answer:

The volume of hydrogen gas produced at s.t.p. is 9.419 dm³

Explanation:

The balanced chemical equation for the reaction is given as follows;

Zn + 2HCl → ZnCl₂ + H₂

Therefore, we have;

One mole of Zn reacts with 2 moles of HCl to produce one mole of ZnCl₂ and one mole of H₂

Number of moles of Zn present = 25/65 = 5/13 = 0.385 moles

Therefore, number of moles of H₂ produced = 0.385 moles

The volume of hydrogen gas produced is given by the relation

PV = nRT, we have;

R = 8.3145 J/(mol·K)

V = nRT/P = 0.385 ×8.3145 ×298.15/(101325)= 0.009419 m³ = 9.419 dm³

The volume of hydrogen gas produced at s.t.p. = 9.419 dm³.


Related Questions

Match the chemical equation with the correct reaction type:
Column A
Column B
1.
Fe +52 - Fe253
2.
Pb(NO3)2 + K2CrO 4 PbCrO 4 +KNO3
a. single replacement
b. double replacement
C. decomposition
3.
H2 + N2 + NH3
d. combustion
4.
Fe + CuCl2 - FeCl2 + Cu
e synthesis
5.
KCIO3 -KCI + O2
6.
Mg + HCI-H2 + MgCl2
7.
C3Hg + O2 CO2 + H2O
8.
Zn + HCI - ZnCl2 + H2
9.
NH3-N2 + O2
10.
AgNO3 + Cu Cu(NO3)2 + Ag
f70X

Answers

1.

Fe +52 - Fe253

SYNTHESIS REACTION

A synthesis reaction occurs when two or more reactants combine to form a single product.

2.

Pb(NO3)2 + K2CrO 4 PbCrO 4 +KNO3

DOUBLE REPLACEMENT

A double-replacement reaction exchanges the cations (or the anions) of two ionic compounds.

3.

H2 + N2 + NH3

SYNTHESIS REACTION

A synthesis reaction occurs when two or more reactants combine to form a single product.

4.

Fe + CuCl2 - FeCl2 + Cu

SINGLE REPLACEMENT

A single-displacement reaction, is a chemical reaction in which one element replaces an/other element in a compound.

Note. An element can only replace an element that it is higher than in the electrochemical series or an element that is less reactive than itself.

5.

KCIO3 -KCI + O2

DECOMPOSITION REACTION

A decomposition reaction is a reaction in which a compound breaks down into two or more simpler substances.

Most times this type of reaction requires an in put of energy.

It is usually an endothermic reaction as heat is mostly absorbed.

6.

Mg + HCI-H2 + MgCl2

SINGLE REPLACEMENT

A single-displacement reaction, is a chemical reaction in which one element replaces an/other element in a compound.

Note. An element can only replace an element that it is higher than in the electrochemical series or an element that is less reactive than itself.

7.

C3Hg + O2 CO2 + H2O

COMBUSTION REACTION

Combustion reaction is a high-temperature exothermic redox chemical reaction between a fuel (example propane C3H8) and an oxidant, usually atmospheric oxygen, that produces oxidized, often gaseous products.( mostly C02)

It can also be referred to as burning.

Combustion reaction is one of the chemical characteristics of hydrocarbons.

8.

Zn + HCI - ZnCl2 + H2

SINGLE REPLACEMENT

A single-displacement reaction, is a chemical reaction in which one element replaces an/other element in a compound.

Note. An element can only replace an element that it is higher than in the electrochemical series or an element that is less reactive than itself.

9.

NH3-N2 + O2

DECOMPOSITION REACTION

A decomposition reaction is a reaction in which a compound breaks down into two or more simpler substances.

Most times this type of reaction requires an in put of energy.

It is usually an endothermic reaction as heat is mostly absorbed.

10.

AgNO3 + Cu Cu(NO3)2 + Ag

f70X

SINGLE REPLACEMENT

A single-displacement reaction, is a chemical reaction in which one element replaces an/other element in a compound.

Note. An element can only replace an element that it is higher than in the electrochemical series or an element that is less reactive than itself.

Which of the following properties would helium have?
A. Closely packed and structured particles
B. Fills entire container
C. Definite volume
D. Definite shape
Reset Selection

Answers

Answer:

B

Explanation:

It is a gas and therefore according to particle model of matter it has large spaces between them and does not have a definite shape

Among the following properties, Helium would fills entire container. Hence Option (B) is correct.

What is States of Matter ?

A “state of matter” is a way to describe the behaviour of atoms and molecules in a substance.

There are three common states of matter: Solids – relatively rigid, definite volume and shape. In a solid, the atoms and molecules are attached to each other. They vibrate in place but don't move around.

Helium is a gas in nature and thus fills entire container.

Therefore, Among the following properties, Helium would fills entire container. Hence Option (B) is correct.

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Convert 16.7 inches to yards (there are 3 feet in a yard)
Using the method of dimensional analysis

Answers

Answer:

Explanation:

16.7 inches [1 foot / 12 inches] [1 yard / 3 feet] Notice how the units cancel each other out. You do have numbers in the denominator. What you get, looks like this

16.7

------

(12 * 3)

16.7 / 36

0.4639 yrds

What is the order, plz answer

Answers

Answer:

C A B

Explanation:

come on, you also know this from normal water waves.

which ones are stronger (= have more energy) ? the small ones or the big ones ?

and the same applies to all waves. the bigger the waves (higher amplitude), the more energy.

Which best describes the importance of the microscope to the development of the cell theory?

Answers

Answer:

The answer is "all the cells are too small, which is not seen by the naked eye, that's why we use a microscope to see it".

Explanation:

In the given question the choices were missing so, we define the correct answer only.

Cells are the essential building blocks of all living entities. There will be trillions of cells within the body. They construct a body shape, absorb nutrients, transform them into energy, and conduct specialized features.  

It provides stability and guidance, encourages mitotic cell development, encourages active and passive transfer, generates energy, induces metabolic processes, and contraceptive support.

what is mean by vector​

Answers

Answer:

A quantity having direction as well as magnitude is called vector.

In 1838 botanist Matthias Schleiden determined that all plants are composed of cells. In 1839, anatomist Theodor Schwann proposed that all animals are composed of cells. In 1855, biologist Rudolph Virchow added to Schleiden's and Schwann's observations and proposed that all living things are composed of cells. Which statement is also part of Virchow's cell theory?

Answers

Answer:

cells arose from preexisting cells

Explanation:

Rudolph Virchow is a German biologist that built on the work of other scientists such as Theodor Schwan to contribute his own quota to the development of the cell theory as it is currently known.

After several studies, Virchow rejected the idea of spontaneous generation and accepted the initially rejected idea of cell division. He earlier believed that cell division only takes place is some special type of cells and not in all cells.

Even though Virchow was not the first to bring the idea of cells arising from preexisting cells, he was the one that popularized the idea and added it to the earlier belief that all living organisms are made up of cells.

Answer:

B

Explanation:

Give two examples of neutralization

Answers

Answer:examples for neutralization - treating indigestion,treatment for insect bites.hope it help you

Explanation:

Cho 17,7 gam kim loại Fe tác dụng với dung dịch HCl loãng, dư thu được V lít khí H2
a) Viết PTHH và tính giá trụ của V
b) Cho lượng Fe ở trên tác dụng với dung dịch H2SO4 đặc nóng, dư thấy thoát ra V1 lít khí SO2. Viết PTHH và tính giá trị của V1

Answers

Answer:

A

Explanation:

خثحصزصزصوصخصزصنثهبخبخلنلولزفكقطيجحسظصمصمسنيبنبهؤخءمقز

For the set of ionic compounds, CaSO4, CaCO3, Ca(OH)2, choose the correct characterization of their solubilities in water from the response list. Group of answer choices None of the three salts are soluble. All three salts are soluble. Two of the three salts are soluble. One of the three salts is soluble.

Answers

Answer:

None of the three salts are soluble.

Explanation:

According to the solubility rule, the carbonates and sulphates of group two elements are insoluble in water.

All three substances mentioned possess very low solubility in water and can be said to be slightly soluble in water. If we compare them with other ionic substances that dissolve readily in water, we can rightly say that they are insoluble in water.

Hence all three substances are insoluble in water.

The melting points of ionic compounds _____

Answers

Explanation:

ionic compounds have high melting points

If each geometric shape represents a different type of atom, and atoms that are touching have chemically bonded with each other, which best describes this model? * 1. An element 2. A compound 3. A homogeneous mixture of two compounds 4. A heterogeneous mixture of two compounds 5. A homogeneous mixture of four elements 6. A heterogeneous mixture of four elements

Answers

Answer:

The correct option is;

3. A homogeneous mixture of two compounds

Explanation:

An homogeneous mixture is one where the components of the mixture are evenly dispersed such that the individual components cannot be seen to be isolated and distinguishable and having a constant composition of the constituents

The image displays three atoms (red circle, cyan triangle, and orange rectangle). The red circle appear to be bonded in pairs while the cyan triangles are bonded to the orange rectangles making a total of two compounds

The arrangement of the compounds in the mixture appear to be very evenly distributed to suggest an homogeneous mixture

The visibility of the compounds should be for an illustrative purpose.

CH4 + 2O2 → CO2 + 2H2O In the chemical reaction, if 10 moles of H2O are produced, moles of CO2 are also produced

Answers

Answer:

The correct answer is 5 moles of CO2 are produced.

Explanation:

The given reaction:  

CH₄ (g) + 2O₂ (g) ⇔ CO₂ (g) + 2H₂O (g)

The given reaction is an illustration of a combustion reaction. Any reaction in which a substance is burnt in excess of oxygen to generate water and carbon dioxide is termed as a combustion reaction. From the given equation, it is clear that the moles of the formation of the products are in the ratio 1: 2, that is, if 10 moles of H₂O is produced, the production of 5 moles of CO₂ will be produced.  

Let us multiply, the given equation with 5 we get,  

5CH₄ + 10O₂ ⇔ 5CO₂ + 10H₂O

Hence, it is clear that with the formation of 10 moles of H₂O, formation of 5 moles of CO₂ will also take place.  

Was is meant by the term suprenatural? Does science deal with the supernatural?

A. The term supernatural literally means (within nature) Science deals with the supernatural because it works within nature, not above it

B. The term supernatural literally means (above nature) Science does not deal with the supernatural because it works within nature, not above it

C. The term supernatural literally means (within nature) Science does not deal with the supernatural because it works above nature, not within it

D. The term supernatural literally means (above nature) Science deals with the supernatural because it also works with nature, not within it

Answers

Answer:

it's option D

Ethane- (-89) Butane- (0) Methanol- (64.7) Hexane- (69) Pentadecane- (270) Heptadecane- (302) a) A mixture of pendtadecane and heptadecane can be separated by______ b) Which pair of compounds are easiest to separate (i) Ethane and Pentadecane (ii) Ethane and Heptadecane (iii) Butane and Hexane (iv) Butane and Heptadecane

Answers

Answer:

(ii) Ethane and Heptadecane

Explanation:

The separation of all the species listed in the answer options for the question depends on the molar mass of each specie.

Ethane is a low molecular mass gas. It exists in the gaseous state at room temperature. However, heptadecane appears as a liquid because it has a greater relative molecular mass.

It is very easily to distinguish between the gas, ethane and the liquid heptadecane which is a high molecular mass alkane, hence the answer.

Which of the following is NOT the property of a non-metal? A. Non-rigid structure B. Not ductile C. Low density D. Malleable

Answers

Answer:

The answer is D.

Explanation:

Malleable is the property of metal not non-metal.

Answer:

malleable

Explanation:

because a non metal cannot be harmmed into sheets

An aerospace engineer is designing a rocket to have three stages. Which is
not a reasonable explanation for this decision?
A. To simplify the design of the rocket
O B. To decrease the mass of the rocket as it flies
C. To take advantage of the lesser amount of thrust needed in space
D. So the rocket only carries necessary mass​

Answers

Answer:

A. To simplify the design of the rocket.

Explanation:

3 stage rockets require huge amounts of fuel when launched in order to last the entire voyage.

As the rocket flies, some compartments may be detached and fall away from the rocket, decreasing its mass (eliminating B, as it is reasonable). This is done so that the rocket only carries necessary mass, which doesn't include the used up rocket parts (eliminating D, as it is reasonable). When the rocket finally reaches space, the decrease in gravity means less thrust is needed, which is an important thing to take note of while designing the rocket (eliminating C, as it is reasonable).

A three stage rocket is very complex and has many features and mechanisms that are complicated to add and deal with. Giving a rocket, three stages is not a simplification, so A is the answer.

A. To simplify the design of the rocket

What is the best design for a rocket?

At supersonic speeds (faster than the velocity of sound), the great shape is a narrower and sharper point. Rockets with a bigger diameter have greater drag because there's greater air being driven out of the manner.

Designing A Rocket In Six Easy Steps is given below

Step One: Know What Your Rocket Needs to Do. Step Two: Establish Mission Parameters. Step Three: Call in Experts. Step Four: Start Drawing. Step Five: Whittle Down the Possibilities. Step Six: Pick the Best Design.

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what are two consents in this experiment
The number of cricket chirps
The temperature of each container
The kind of containers used
The number of crickets in each container

Answers

Answer:

the number of crickets in each container

Explanation:

to participate in the experiment you will have to know the crickets in the container

Which element increases its oxidation number in this reaction? 3KOH + H3PO4 → K3PO4 + 3H2O

Answers

Answer:

The answer is "no changes in oxidation number "

Explanation:

Given equation:

[tex]3KOH + H_3PO_4 \longrightarrow K_3PO_4 + 3H_2O[/tex]

In the above-given equation, there are no changes in the oxidation number which can be defined as follows but first we defined the oxidation: In the chemical process, it requires the transfer of ions is oxidation. In particular, it means that products that supply electrodes are oxidized. In the given equation, when 3Potassium hydroxide reacts with phosphoric acid it will produce potassium phosphate and 3 moles of water.

 

Which is not a characteristic of all metals? Select one: a. soft and easy to cut b. Good electrical conductors c. Ductile and malleable

Answers

The answer is option a.soft and easy to cut


Hope it helps
And if it does pls mark as brainliest

You work in the special effects department of a movie studio. You are
currently working on a superhero movie where the hero is very strong
and can punch through metal. For the next scene you need to replace a
6 inch by 6 inch square of a metal wall with a different material that will
crumble when the actor hits it. What could you use?

A. You could use Carbon(C)
B. You could use Potassium (k)
C. You could use Titanium (T)
D. You could use Manganese (Mn)


Answers

Answer:

The correct option is;

D. Manganese (Mn)

Explanation:

Manganese is very brittle, hard, iron like silvery-gray metal, that is difficult to melt. In air, Manganese slowly disintegrate in a similar manner to iron rusting in water

Manganese and iron have similar chemical and physical properties however manganese is more harder and more brittle than iron

A brittle material is one that easily breaks without deforming elastically

Therefore, manganese, due to its very iron like appearance and brittle nature will be suitable to replace the metal wall and crumble easily when the actor hits it.

[tex]v=0.164m*8.3cm*12.4cm[/tex]

Answers

Answer:

helloooo

0.164m * 100 = 16.4 cm

now multiplying all of em

v = 1,687.888

Sulphur dioxide is a common pollutant from burning coal.State two effects caused by this pollutant and also write the chemical equation.

Answers

Heya!

Sulfur dioxide - ( SO2 )

Answer:

Sulfur dioxide is a common pollutant caused due to the burning of coal,Is very harmful for the environment and health.

Effects:

Health effects-Sulfur dioxide effects the respiratory system which includes the functioning of lungs,respiratory track and causes infections,can also effect  and irritate the eyes and causes aggravating conditions such as asthma and chronic bronchitis.As most sulfur dioxide air pollution comes from the burning of coal and oil in power plants. It is a emitted by trains, large ships and other diesel objects that burns alota   sulfur fuel so this also effects the environment like plants and others as the air lacks oxygen ,but with more sulfur dioxide.

Hope this helps!

Have a nice day!:)

hurry
A solution:

A. is a mixture that is made when a solid dissolves and combines with a liquid.

B. is the amount of a substance that will combine with another substance before they begin to chemically combine.

C. is the amount of a substance that will dissolve in 1 dm3 of water at 25 C .

D. is two or more substances that are combined together but not chemically joined.

Reset Selection

Answers

Answer:

b is the correct answer ok

A solution is made up of solute and solvent. It is an addition of two or more substances to each other that combines physically and chemically. Thus, option B is correct.

What is a solution?

A solution is the mixture of solutes that can be more than one in a solvent that has the same composition all over (homogenous). A solution comprises two main elements called a solute and a solvent.

A solute is the part of the solution that has been added to the solvent for desolvation. On the other hand, the solvent is the substance that dissolves the solute in them to make a solution.

The homogenous mixture or the solution can be created by mixing salt and water, sugar and water, mercury in amalgamated zinc, coffee, vinegar, etc.

Therefore, option B. a solution is the addition of the substances that combine physically.

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PLZ HELP ME A single bacterial cell divides to make new bacterial cells. Which of the following is true of this kind of reproduction? A Two parents come together to produce offspring with different characteristics
B. Two parents come together to produce offspring that are exact copies of one parent
C One parent produces offspring that are exact copies of the parent
D. One parent produces of sening with different charactenstes SUERT​

Answers

Answer:

its C

Explanation:

When a single salt crystal is added to a cool liquid, large crystals form. Which statement about the original cool liquid is correct?

A) The liquid is a heterogeneous mixture because the crystals can be easily separated from the liquid

B) The liquid is a pure substance because it was made up of a single compound

C) The liquid is a pure substance because it was uniform before the crystal was added

D) The liquid is a homogenous mixture because the substance that formed the large crystals was uniformly dissolved

Answers

The liquid is a homogeneous mixture because the substance that formed the large crystals was uniformly dissolved.

A solution is composed of a solute and a solvent. A solution is a typical example of a homogeneous mixture.

We define a solution as any combination of solute and solvent. A solution can be regarded as a homogeneous mixture since the solute is uniformly distributed throughout the solution. The solute and solvent constitutes one phase.

When a salt crystal is added to the solution, crystallization is induced and large crystals of solute form.

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A salt crystal is a cubic form of sodium chloride that is closely bounded together by the reaction of sodium and chlorine ions during electrovalent bonding.

Taking a look at a heterogeneous mixture;

It refers to the mixtures that are not thoroughly mixed and uniform in composition.

On the other hand, homogeneous mixtures are formed when a substance i.e. solute (here, it is the salt crystal) is being added to a cool liquid(solvent) is thoroughly mixed.

From the given information, we are being told that when this single salt crystal is added to the cool liquid, large crystals are formed.

This implies that the formation of large crystals is brought about by the action of crystaliization rendering the liquid to be a homogeneous mixture.

We can therefore conclude that the correct statement about the original cool liquid is in Option D.

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calculate the pH of 500cm3 of 0.2mol/dm3 Ca(OH2), assume complete ionisation​

Answers

Answer:

The pH of 500 cm³, 0.2 mol/dm³, Ca(OH₂) is ≈ 13.6

Explanation:

The given parameters are;

Concentration of the calcium hydroxide, Ca(OH₂) = 0.2 mol/dm³

Volume of the calcium hydroxide, Ca(OH₂) = 500 cm³

Given that the calcium hydroxide, Ca(OH₂),  undergoes complete ionization in water, complete dissociation, we have;

Ca(OH₂)  ⇄  Ca²⁺ + 2 OH⁻

Therefore, we have;

2 moles of [OH⁻] for each mole of Ca(OH₂) which gives the concentration of  [OH⁻] as

[OH⁻] = 2 × 0.2 ≈ 0.4 mol/dm³

The pH is given by the formula

pH = 14 + ㏒₁₀ [OH⁻]

pH = 14 + ㏒₁₀ (0.4) = 14 - 0.3979 = 13.6021 ≈ 13.6

The pH of the 500 cm³ 0.2 mol/dm³ Ca(OH₂) ≈ 13.6.

What is the equilibrium constant of aA+bB cC +dD?

Answers

Explanation:

{c}^C . {d}^D / {a}^A . {b}^B

If the red car travels from 50 m to -25 m in 5 seconds, what is its velocity?

Answers

Answer:

V = 14m/s

Explanation:

velocity is the rate of change in displacement

V = (change in displacement)/time

V = (50 - (-20) )/5

V = (70)/5

V = 14m/s

Which of the following is an example of combustion?
O A. potassium chlorate -> potassium chloride + oxygen
B. aluminum + cobalt chloride -> aluminum chloride + cobalt
O c. hexane + oxygen carbon dioxide + water
OD. sodium cyanide + hydrochloric acid -> sodium sulfate + hydrogen cyanide

Answers

The answer is c hexane+oxygen carbondioxide+ water
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