What would be the cathode in a magnesium and zinc galvanic cell?
O A. Mg2+
OB. Zn(s)
OC. Zn²+
OD. Mg(s)

Answers

Answer 1

The correct answer is C. Zn²+. In a magnesium and zinc galvanic cell, the anode is the magnesium (Mg(s)) and the cathode is the zinc (Zn²+).

What is zinc galvanic cell?

A zinc galvanic cell is an electrochemical device that uses a zinc anode and a cathode of a different material, usually copper, to produce electricity. The reaction that occurs in the cell is a redox reaction, which involves the oxidation of zinc at the anode and the reduction of copper at the cathode.

Zn²+. In a magnesium and zinc galvanic cell, the anode is the magnesium (Mg(s)) and the cathode is the zinc (Zn²+). In this cell, the magnesium metal is oxidized to form Mg2+ ions which are released into the solution. The zinc ions (Zn²+) are then reduced to zinc metal (Zn(s)) at the cathode.

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Answer 2

Answer: B

Explanation:


Related Questions

1 atm = 760 torr
For isooctane:

For tetramethylbutane:

Answers

There is no other feasible arrangement of “tetramethylbutane” it is redundant in this circumstance.

What is Tetramethylbutane?

Tetramethylbutane, often known as hexamethylethane, is a hydrocarbon with the chemical formula C8H18 or (H3C-)3C-C(-CH3)3. It is the most branching and compact of the several octane isomers, as well as the only one having a butane (C4) backbone.

It has a highly symmetrical structure, a high melting point, and a narrow liquid range; in fact, it is the smallest saturated acyclic hydrocarbon that emerges as a solid at 25 °C. (Cubane, C8H8, is much smaller and solid at room temperature among cyclic hydrocarbons.) It is also the most stable C8H18 isomer, with a lower heat of formation of 4.18 kcal/mol (17.5 kJ/mol) than n-octane, which has been related to dispersive interactions (electron correlation) between the methyl groups (protobranching).

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3. Silances are more reactive than alkanes. Explain.

Answers

The lower bond energy of the silicanes make them more reactive than the alkanes.

What are the silicanes?

We know that the members of group four has the ability to catenate and this is a property that characterizes all the elements that we can find in the group. However the extent to which the members of the group can be able to catenate is what we use to determine the stability of the bonds.

The alkanes are composed of the bonds that exist between carbon and hydrogen and the alkanes can be able to form very long chains and this can be used to explain the fact that you can be able to find the alkanes in various kinds of applications.

However, the bond energy of the silicanes is less than that of the alkanes hence they tend to be more reactive  then the alkanes.

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the maximum allowed concentrations of chloride in municipal drinking water supply in 250 ppm cl. when the supply of water exceeds this limit it often has a distinctive salty taste. what is the concentration in molarity?

Answers

The allowed concentration of Cl in water is 250 ppm. Then the equivalent concentration in molarity is 0.007 molar.

What is molarity ?

Molarity is a common term used to express the concentration of a solution. It is the ratio of the number of moles of solute to the volume of solution in liters. Molarity is a temperature dependent measurement.

Parts per million is another term of concentration have the formula as written below:

ppm = ws/W × 10⁶

Where, ws is the weight of solute and W be the weight of solution in grams.

1 molar = 35500 ppm

therefore, 250 ppm = 250 ppm × 1M /35500 ppm  = 0.007 M.

Hence, the molarity of the salt solution will with the maximum  allowed concentration will be 0.007 M.

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What would be the electron configuration for neutral oxygen? Please show what energy level each electron is in using the electron diagonal filling rule do not use noble gas configuration.

Answers

Answer: 1s2 2s2 2p4

Explanation:

Recall the number of electrons an orbital can have:

s orbitals have 2, p orbitals have 6, d orbitals have 10, f orbitals have 14, and so on.

Oxygen in its neutral state would have 8 electrons.

To summarize the diagonal filling order, it goes from the least energy level to the most, and the orbital with the least amount of orbitals to the most.

So, the order for this will go from 1 and end at 2 (for energy level,) then s, s again (as energy level 1 has 1s orbital only,) and p.

So, the first energy level, 1s2 (2 electrons), leaves the remaining six electrons.

Completely fill the s orbital (another 2 electrons), and the remaining 4 electrons will be in the respective p orbital.

Thus, it is 1s2 2s2 2p4.

Please help me I really need the help

Answers

Thermal energy is the sum of all the potential and kinetic energy of the atoms within a system that is responsible for its temperature.

How to conclude the Electro negativity?

Friction transforms other forms of energy into thermal energy. Atoms are the building blocks of matter. Atoms are composed of subatomic particles called protons, neutrons, and electrons.Periodic trends are patterns on the periodic table that illustrate elements’ characteristics.Significant trends are atomic radius, metallic reactivity, electronegativity, electron affinity, and ionization energy.

Atomic radius and metallic reactivity trends: They increase when they move down a group and left across a period.Electronegativity, electron affinity, and Ionization energy trends: They increase when they move up a group and right across a period.

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Why do some elements not take part in chemical bonds?

Answers

Answer:

Because there is some element which is already in an octet state and has no need to achieve it, they have a full electron in their outermost shells such as helium, argon etc.

C(s) + O2(g) → CO2(g) ΔHº = -94.6 kJ

H2(g) + \scriptsize \frac{1}{2}O2(g) → H2O(l) ΔHº = -286.0 kJ

2C2H2(g) + 5O2(g) → 4CO2(g) + 2H2O (l) ΔHº = -2598.8 kJ

calculate the value of ΔHº for the final reaction:

2C(s) + H2(g) → C2H2(g) ΔHº = kJ

Answers

The value of enthalpy(ΔHº) for the final reaction (2C(s) + H₂(g) → C₂H₂(g) ) is  -1932.8KJ.

Enthalpy change: what is it?

A system's enthalpy is its heat capacity. A reaction's enthalpy change is roughly equivalent to how much energy is lost or gained throughout the reaction. If the enthalpy of the system decreases over the reaction, the reaction is preferred.

C(s) + O₂(g) → CO₂(g) ΔHº = -94.6 kJ --- (1)

H₂(g) + O₂(g) → H₂O(l) ΔHº = -286.0 kJ ---(2)

2C₂H₂(g) + 5O₂(g) → 4CO₂(g) + 2H₂O (l)  ΔHº = -2598.8 kJ ---(3)

The value of ΔHº for the final reaction,

2C(s) + H₂(g) → C₂H₂(g)

ΔH₄° = 2× ΔH₂º +  ΔH₃º - ΔH₁º
ΔH₄° = 2× -286.0 + ( -2598.8) - (- 94.6)

ΔH₄° = 2× -286.0 -2598.8 + 94.6

ΔH₄° = 666 - 2598.8

ΔH₄° = -1932.8KJ.

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How many moles of gas are present if P=1atm, V=1L, T=1K?
it depends on the chemical's molar mass
O.12
8.314
01

Answers

The number of moles of the ideal gas is 0.12 moles. Option A

What is the number of moles?

In the context of the problem that we have here, we are looking at the ideal  gas equation. When we look at the idea gas equation, we can tell that we would have the pressure of the gas, the volume of the gas as well as the temperature of the gas in view as is the case that we have here.

Thus, the idea that we are asked to pass across in the question is that we should be able to find out the number of moles that we have in the compound that have the variables that have been listed here.

Pressure (P) =  1 atm

Volume (V) = 1 L

Temperature (T) = 1 K

Number of moles (n) = ?

Using;

PV = nRT

n = PV/RT

n = 1 * 1/0.082 * 1

n = 0.12 moles

The moles of the gas is 0.12 moles.

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A student placed four magnets of equal size and mass each the same distance from an electromagnet. She turned the electromagnet on and then quickly turned it off. The diagram below shows how far each magnet traveled toward the electromagnet when the circuit was closed.

four magnets near an electromagnet
What is the order of the magnets by strength from strongest to weakest?

magnet W
magnet X
magnet Y
magnet Z
You have to put them in order

Answers

Four magnets near an electromagnet What is the order of the magnets by strength from strongest to weakest. magnet W,magnet X,electromagnet,magnet Y,magnet Z.

What is electromagnet?

An electromagnet is a type of magnet in which the magnetic field is generated by an electric current. It usually consists of a coil of wire that is wrapped around a core of magnetic material such as iron or steel.

When an electric current passes through the wire, a magnetic field is created around the core, making it a magnet. Electromagnets are used in many different applications, such as motors, generators, and speakers.

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an oxygen atom, the number of nucleons is 16. What is its atomic mass?​

Answers

Answer:

oxygen-16 is a stable isotope of oxygen, having 8 neutrons and 8 protons in its nucleus. It has a mass of 15. u

A relationship that decreases the dependent variable when the independent variable increases is called __________________

Answers

molecule of the variables shift in the opposite directions when there is a inverse or negative relationship. In other words, the dependent variable grows if the value of the independent variable falls.

What is the name of the correlation here between dependent and independent variables?

The dependent variable in this study are often the effect and the variable are the cause in a research investigation. Additionally, one could say that there is a cause-and- effect link between the independent and the dependent variables.

What kind of link does there exist between these two variables?

A statistical method known as correlation is used to quantify and explain a link between two variables. The two factors are often just observed, not changed. Two scores from identical people must be used for the correlation

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Question (1 point)
Given the model, answer the following questions regarding effusion. The orange spheres have a greater root-mean-square speed than the blue spheres. Assume the balloon has a tiny opening for gas molecules to escape.
1st attempt
Part 1 ( 0.5 point)
See Periodic Table See Hint
Which balloon, A or B, most accurately illustrates the effusion of a gas from the central balloon?
Calculate the relative rate of effusion for the orange to blue spheres. The root-mean-square speed for the orange spheres is 495.0m/s. The root-meah-5quare speed for the blue spheres is 380.0m/ s.

Answers

According to the claim, Balloon A, which has more blue and less orange, exhibits accurate effusion at a relative effusion rate of 1.303. (orange is 1.303 times more effused than blue).Relative rate of effusion for the orange to blue spheres = 1.531.

What is effusion ?

The process of effusion is when a gas escapes from a container through a hole that is significantly smaller in diameter than the molecules' mean free path.

Gas molecules flow through a small opening in one container and into another by effusion. Graham's law allows rates of effusion to be compared at the same temperature. Diffusion is the random molecular motion-based movement of gas molecules through one or more other types of gas.

Rate of effusion of Orange / Rate of effusion of blue

= [Mblue / Morange]^1/2

Vrms = sqrt [(3RT/M)]

Vorange / Vblue = [ Mblue / Morange]^1/2

Rate of effusion of Orange / Rate of effusion of blue

= 565/ 369

= 1.531

Thus,  Balloon A, which has more blue and less orange, exhibits accurate effusion at a relative effusion rate of 1.303.

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CHEMISTRY - DOES ANYONE KNOW HOW TO DO THIS QUESTION???

Answers

Cathode: 2 Ag+ (aq) + 2 e- → 2 Ag (s). Anode: 2 H+ (aq) → H2 (g) + 2 e-.

What is cathode ?

A cathode is an electrode in an electrical circuit from which electrons flow out. It is usually made of metal and is negatively charged. Cathodes are commonly used in electronic devices such as batteries, lamps, and vacuum tubes. In a battery,

the cathode is the terminal which provides a negative charge and is usually connected to the negative terminal of the battery. In a vacuum tube, the cathode is the source of electrons which flow through the tube to the anode, which is the positive terminal.

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how do you test the methods of cleaning an oil spill while not risking the lives of the organisms

Answers

Answer:

Get a controlled environment, such as a pool or even a bowl. Pour some oil in it then you can test your solutions without causing any damage.

Explanation:

What is the molecular weight of H2O

Answers

Answer:

18.015

Explanation:

Using the periodic table of the elements to find atomic weights, we find that hydrogen has an atomic weight of 1, and oxygen's is 16. In order to calculate the molecular weight of one water molecule, we add the contributions from each atom; that is, 2(1) + 1(16) = 18 grams/mole.

What mass of O2 molecules contains the same number of oxygen atoms as 14.0 g of water?

Answers

Answer:

So 0.39 moles of oxygen are produced in 14 g of water. So that's it.

Explanation:

O
Question 2 of 10
Which of the following values best classifies a bond between 2 atoms as
being covalent?
A. An electronegativity difference of greater than 2.7 between the
atoms
B. An electronegativity difference of greater than 1.7 between the
atoms
C. An electronegativity difference of less than 1.7 between the atoms
D. An electronegativity difference of less than 2.7 between the atoms
← PREVIOUS
SUBMIT

Answers

A bond between 2 atoms as being covalent an electronegativity difference of greater than 1.7 between the atoms.

What is bond?

Bond is a debt instrument, which is issued by governments and corporations. These bonds are used to raise capital for various projects and investments. Bonds are a form of loan and investors are usually paid a fixed interest rate for lending their money. Bonds are typically issued for a fixed period of time, usually for a period of 5-30 years, and have a fixed maturity date. Investors receive interest payments at regular intervals and receive the principal amount of the bond at the end of the period.

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What is the name of the charge that orbits the nucleus called?

Answers

Answer:

Electrons

Explanation:

"An electron is a negatively charged particle that orbits the nucleus of an atom."

"Electrons are negatively charged particles arranged in orbits around the nucleus of an atom"

What is the mass of a 8.45 m3 piece of copper?

Answers

The mass of a 8.45 m3 piece of copper is 7537.4 grams.

What is mass?

Mass is described as a dimensionless quantity representing the amount of matter in a particle or object.

density of copper =8.92g/cm^3

volume = 8.45 x 100 cm^3

mass =  (8.45 x 100) x 8.92

mass = 7537.4 grams.

The relationship between mass, density and volume is that density offers a convenient means of obtaining the mass of a body from its volume or vice versa.

This means that the mass is equal to the volume multiplied by the density (M = Vd), while the volume is equal to the mass divided by the density (V = M/d).

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what is van't hoff factor?
state the formulas to calculate " i " during association or dissociation.

tysm! :)​

Answers

The relationship between the calculated concentration of a material and the actual concentration of particles is known as the Van't Hoff factor.

I is the difference between a typical or theoretical colligative quality and an observable one.

What does the connection van t Hoff factor mean?

The van 't Hoff factor is the difference between the concentration of a material determined by its mass and the concentration of particles actually formed when the substance is dissolved. The van 't Hoff factor is virtually 1 for the majority of non-electrolytes dissolved in water.

What does Van t Hoff factor mean in terms of connection and dissociation?

For dissociation, association, and the non-electrolyte solute, the Van't Hoff factor value is more than one, less than one, and equal to one respectively.

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PROBLEM 1.22 Give the hybridization state of each carbon in the following

compounds:

(a) Carbon dioxide (0 = C = O)

(d) Propene (C*H_{3}*CH = C*H_{2})

(b) Formaldehyde (H_{2}*C = O)

(e) Acetone [(CH 3 ) 2 C = OI

(c) Ketene (H_{2}*C = C = O)

(f) Acrylonitrile ( C*H_{2} =CHC equiv N)

SAMPLE SOLUTION

(a) Carbon in C*O_{2} is directly bonded to two other atoms. It

is sp-hybridized.

Answers

To solve this we must be knowing each and every concept related to hybridisation. Therefore, the hybridisation of the given molecule can be given as below.

What is hybridisation?

Only during bond formation does hybridization occur, not in an individual gaseous atom. If the bonding of a molecule is known, the geometry of the molecule may be predicted.

compound                                                              hybridisation

Carbon dioxide (0 = C = O)                                       sp

Propene (CH[tex]_3[/tex]CH = CH[tex]_2[/tex])                                            sp³, sp²,sp²

Formaldehyde (H[tex]_2[/tex]C = O)                                             sp²

Acetone [(CH[tex]_3[/tex] )[tex]_2[/tex] C = O                                                 sp³, sp²,      sp³

Ketene (H[tex]_2[/tex]C = C = O)                                                  sp²,    sp

Therefore, the hybridisation of the given molecule can be given as above.

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EXPLAIN Before medical images are taken, radioisotopes are often injected into a vein in a patient’s arm, or the patient drinks a solution containing the radioisotopes. Why do
you think atoms in the body usually do not emit radiation?

Answers

Answer: adioisotopes, are species of chemical elements that are produced through the natural decay of atoms. Exposure to radiation generally is considered harmful to the human body, but radioisotopes are highly valuable in medicine, particularly in the diagnosis and treatment of disease.

Explanation:

Why don’t different varieties of corn plants grow to the same size under similar growing conditions?

Answers

Because they were planted at different times in different conditions

Rank the following fibers on the degree to which a dye will bind to the fabric and resist fading.
rank the following fibers on the degree to which a dye will bind

Answers

Answer:

polymer mear least receptive to dye

,

The reaction below shows the combustion of propane (C3H8). Why is the mole ratio (3 moles CO2/1 mol C3H8) used to determine the amount of carbon dioxide (CO2) produced when propane (C3H8) combusts in excess oxygen? (1 point) C3H8 + O2 yields CO2 + H2O + heat Propane has a mass that is 3 times greater than that of CO2, so only 1 mole of C3H8 is needed to produce 3 moles of CO2. When the chemical equation for propane combustion is balanced, 1 mole of C3H8 is needed to produce 3 moles of CO2. During combustion, CO2 is approximately 3 times more reactive than C3H8, so less C3H8 will participate in the reaction. Carbon dioxide has a volume of about one-third that of C3H8, so 3 moles of CO2 are needed to react with each mole of C3H8.

Answers

One mole of the propane produces three moles of the carbon dioxide from mole ratio.

What is the mole ratio?

When we talk about the mole ratio, we mean the ratio of the species that can be found in the reaction. We can be able to get the mole ratio from the balanced reaction equation and we apply it to solve problems from the stoichiometry of the reaction.

Given the fact that we have the reaction as it has been written in the question, it is clear that we would need about one mole of the propane to produce three moles of carbon dioxide.

We can see that there are three atoms of carbon in the propane and the implication of this is that we are going to produce three atoms of carbon dioxide in the product.

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What is the density of a 1209 kg object that is 1.94 m3 in size?

Answers

Answer:

623 kgm^-3

Explanation:

Density = Mass/Volume

Mass = 1209 kg

Volume = 1.94 m^3

Density = 1209 / 1.94 kgm^-3

             = 623.1958763 kgm^-3

             = 623 kgm^-3 (3sf)

What is the ratio between the numbers 30 and 90

Answers

the answer is 1:3 ……
30:90
1:3

you can divide it

Are all antigens foreign substances?

Answers

No, not all antigens are foreign substances.

An antigen is any substance that can trigger an immune response, including the production of antibodies. Some antigens are naturally present in the body and are called "self" antigens which are usually not harmful, but in some cases, the immune system can mistakenly recognize them as foreign and attack them which can lead to autoimmune diseases.

Antigens bind together with antibodies and promote the elimination of harmful pathogens present in the body. They alert other parts of the immune system to take over which helps to neutralize the threat from pathogens.

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how many grams of hexane(C6H14) would be need to make 562 of carbon dioxide

Answers

The mass of hexane, C₆H₁₄ that would be needed to produce 562 grams of carbon dioxide, CO2 is 183 g

How do I determine the mass of hexane, C₆H₁₄ needed?

We'll begin by writing the balanced equation for the reaction.

2C₆H₁₄ + 19O₂ → 12CO₂ + 14H₂O

The following are obtained from the equation:Molar mass of C₆H₁₄ = 86 g/molMass of C₆H₁₄ from the balanced equation = 2 × 86 = 172 g Molar mass of CO₂ = 44 g/molMass of CO₂ from the balanced equation = 12 × 44 = 528 g

From the balanced equation above,

528 g CO₂ were produced from 172 g of C₆H₁₄

With the above information, we shall determine the mass of hexane, C₆H₁₄ needed to produce 562 g CO₂. Details below:

From the balanced equation above,

528 g CO₂ were produced from 172 g of C₆H₁₄

Therefore,

562 g of CO₂ will react to produce = (562 × 172) / 528 = 183 g of C₆H₁₄

Thus, the mass of hexane, C₆H₁₄ needed is 183 g

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the enthaply of formation of water is -285.8kj/mol. what can be inferred from this statement

Answers

Answer:   It takes 285.8 kJ of energy to form one mole of water

Explanation:

The enthalpy of formation of a substance is the change in enthalpy that occurs when a substance is formed from its elements in their standard states. The enthalpy of the formation of water is -285.8 kJ/mol, which means that it takes 285.8 kJ of energy to form one mole of water from its elements (hydrogen and oxygen) under standard conditions. This value is negative, which means that the formation of water releases energy. This is why water is often referred to as an "exothermic" substance because it releases energy when it is formed. The negative value of the enthalpy of formation for water can be explained by the fact that the bonds formed between hydrogen and oxygen atoms in water are stronger than the bonds between hydrogen and oxygen atoms in the individual elements. This means that it takes less energy to break the bonds in the elements than it releases when the bonds in water are formed, resulting in a net release of energy.

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Answer:

This means that 285.8 kJ/mol is evolved when one mole of water is formed.

What is the enthalpy of formation?

The term enthalpy of formation has to do with the energy that is released or absorbed when a molecule of water if formed from its constituents.

The fact that the enthalpy of formation of water is -285.8 kJ/mol implies that 285.8 kJ/mol is evolved when one mole of water is formed.

Explanation:

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