Which ionic equation describes a redox reaction? A. Ag(+) + Cl- = AgCl B. 2H(+) + CO3(2-) = CO2 + H2O C. H(+) + OH(-) = H2O D. Zn + Cu(2+) = Zn(2+) + Cu The marking scheme of the past paper this question is from says that the answer is D but how?

Answers

Answer 1

Answer: The correct option is D. [tex]Zn+Cu^{2+}\rightarrow Zn^{2+}+Cu[/tex]

Explanation:

Redox reaction is defined as the reaction in which oxidation and reduction take place simultaneously. It is known as the reaction in which the exchange of electrons takes place.  

The oxidation reaction is defined as the reaction in which a chemical species loses electrons in a chemical reaction. It occurs when the oxidation number of a species increases.

A reduction reaction is defined as the reaction in which a chemical species gains electrons in a chemical reaction. It occurs when the oxidation number of a species decreases.

From the given ionic reactions:

[tex]Zn+Cu^{2+}\rightarrow Zn^{2+}+Cu[/tex]

On the reactant side:

Oxidation number of Zn = 0

Oxidation number of Cu = +2

On the product side:

Oxidation number of Cu = 0

Oxidation number of Zn = +2

As the oxidation number of Zn is increasing from 0 to +2. Thus, it is getting oxidized. Similarly, the oxidation number of Cu is decreasing from +2 to 0. Thus, it is getting reduced. Therefore, forming a redox couple

Hence, the correct option is D. [tex]Zn+Cu^{2+}\rightarrow Zn^{2+}+Cu[/tex]


Related Questions

A teacher brings in a cup of iced water and asks students to discuss if the system is exothermic or endothermic . Aida states the system is exothermic , while Alexander states the system is endothermic .

Answers

Answer:

C

Explanation:

In thermodynamics, a exothermic system looses heat to the surroundings while an endothermic system absorbs heat from the surroundings.

A system is a part the universe marked off by a specified boundary. The contents of the cup constitutes the system in this case.

The region of space outside the system is called the surroundings. Hence everything outside the cup constitutes the surroundings.

state and explain the trends in the atomic radius and ionization energy for elements Li to Cs.

Answers

Explanation:

ionisation energy decrease down the group as the atomic radius increases. Nuclear charge increases. Number of shell increases so the electron will experience more shielding so it would be easier for the atom to loss electron.


13. If a reaction is endothermic,
a) The temperature increases
b) It takes more energy to break the bonds of the reactants than is released when the bonds in
the products are formed
c) More energy is released when the bonds in the products are formed than is used to break
the bonds in the reactants
d) The same amount of energy is used to break the bonds of the reactants as is
released when the bonds in the products are formed

Answers

Answer:

Endothermic reactions are reactions that require external energy, usually in the form of heat, for the reaction to proceed. In order to melt the ice cube, heat is required, so the process is endothermic. Endothermic reactionIn an endothermic reaction, the products are higher in energy than the reactants.

Explanation:

What mass of Na2SO4is needed to make 2.5 L of 2.0 Msolution? (Na = 23 g; S = 32 g; O = 16 g)
a.356 g
b.284 g
c.710 g
d.178 g

Answers

Answer:

mass (g) needed = 710.2 grams Na₂SO₄(s)

Explanation:

Needed is 2.5 Liters of 2.0M Na₂SO₄; formula wt Na₂SO₄ = 142.04g/mol.

mass (grams) of Na₂SO₄(s) = Molarity needed x Volume needed in Liters x Formula Wt of solute

mass (grams) of Na₂SO₄(s) = (2.5L)(2.0M)(142.04g/mol) = 710.2 grams Na₂SO₄(s)

Mixing: Transfer 710.4 grams Na₂SO₄ into mixing vessel and add water-solvent up to but not to exceed 2.5 Liters total volume. Mix until dissolved.

Gives 2.5 Liters of 2.0M Na₂SO₄(aq) solution.

PLEASE HELP ASAP
You have 3 beakers sitting in front of you for a lab, but you forgot to label the beakers. You
do not remember which chemical you put into which beaker, and they are all colourless
solutions. You know that you had hydrogen chloride (HCI), lithium sulfate (Li,SO.), and
Describe two diagnostic tests, including expected results that you could use to identify the
three solutions and allow you to label your beakers

Answers

Answer:

put a salt into the beakers

Mark Brainliest please

For ethanol you test a cereic ammonia nitrate test ethanol gives you blue voilet color so you can easily guess what is ethanol
for HCL you use a NACL which makes a compund neutral so you easily guess it
and rest of it LI2SO4 you can label it

What is the equilibrium expression for the reaction below?
2Na(s) + 02) Na2O2,(s)

Answers

Answer:

[tex]{ \tt{k _{c} = \frac{[Na_{2} O _{2} ]}{[Na] {}^{2} [O _{2} ]} }}[/tex]

How does increasing temperature increase the number of reactions?
A. It increases the length of time the molecules are together.
B. It increases the collisions that have enough energy to react.
C. It makes the orientation of the molecules not important.
D. It lowers the amount of energy needed for a reaction to occur.

Answers

Answer:D. it lowers the amount of evergy needed for a reaction to occur.

Explanation:

a p e x

The concept Arrhenius equation is used here to determine the factor which increases the number of reactions. As the temperature increases, It increases the collisions that have enough energy to react. The correct option is B.

What is Arrhenius equation?

An equation which represents the relationship between the activation energy and rate of the reaction is known as the Arrhenius equation. According to this concept, lower the activation energy of a reaction, the higher its rate will be.

The equation is:

[tex]k = A . e^{-} ^{E_{a} } / RT[/tex]

k - Rate constant

A - Frequency factor

Eₐ - Activation energy

R - Gas constant

T - Temperature

When the temperature increases, the energy and speed of the molecules increases which in turn increases the number of effective collisions. If greater the value of frequency of collisions, then value of 'k' will be higher and greater is the number of reactions.

Thus the correct option is B.

To know more about rate of a reaction, visit;

https://brainly.com/question/30546888

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What must happen for an electron to return to its original energy level from a
higher energy level?

A. It must release photons.
B. It must absorb photons.
C. It must absorb electrical energy.
D. It must emit electrical energy.

Answers

Answer:

c

Explanation:

it must absorb electrical energy

You're a dentist and want your patients to have the cleanest smiles possible. You're not sure which toothpaste to recommend and decide to design an
experiment to determine which toothpaste gives the brightest and whitest smile.
1) What variables would you need to control in your
experiment?
2) Which variable would you change to determine which toothpaste is best?
3) What is the measurable outcome for this experiment?
d) What would the procedure be for your experiment? Please help me to answer this questions:(

Answers

Answer:

Why do you need good toothpaste?

Explanation:

Answer:

Do this yourself smh this isnt what the wesite is for

Explanation:

An aqueous sodium acetate, NaC2H3O2 , solution is made by dissolving 0.395 mol NaC2H3O2 in 0.505 kg of water. Calculate the molality of the solution.

Answers

Answer: The molality of [tex]NaC_2H_3O_2[/tex] solution is 0.782 m

Explanation:

Molality is defined as the amount of solute expressed in the number of moles present per kilogram of solvent. The units of molarity are mol/kg. The formula used to calculate molality:

[tex]\text{Molality of solution}=\frac{\text{Moles of solute}}{\text{Mass of solvent (in kg)}}[/tex] .....(1)

Given values:

Moles of [tex]NaC_2H_3O_2[/tex] = 0.395 mol

Mass of solvent (water) = 0.505 kg

Putting values in equation 1, we get:

[tex]\text{Molality of }NaC_2H_3O_2=\frac{0.395mol}{0.505kg}\\\\\text{Molality of }NaC_2H_3O_2=0.782m[/tex]

Hence, the molality of [tex]NaC_2H_3O_2[/tex] solution is 0.782 m

Give an example of a reaction where the following are involved:
(a) Heat
(b) Light
(c) Electricity
(d) Close contact
(e) Solution
(f) Pressure
(g) Catalyst​

Answers

Explanation:

everything can be found in the picture

What is the volume of 0.200 mol of an ideal gas at 200. kPa and 400. K?
Use P V equals n R T. and R equals 8.314 StartFraction L times kilopascals over moles time K EndFraction..

Answers

3.3256 Liters

See the image I have shared to you above

Answer:

B. 7.2k

Explanation:

took the test ;)

When heat is applied to 80 grams of CaCO3, it yields 39 grams of B. Determine the percentage of the yield.

Answers

The question is incomplete, the complete question is:

When heat is applied to 80 grams of CaCO3, it yields 39 grams of CaO Determine the percentage of the yield.

CaCO3→CaO + CO2

Answer: The % yield of the product is 87.05 %

Explanation:

The number of moles is defined as the ratio of the mass of a substance to its molar mass.

The equation used is:

[tex]\text{Number of moles}=\frac{\text{Given mass}}{\text{Molar mass}}[/tex] ......(1)

We are given:

Given mass of [tex]CaCO_3[/tex] = 80 g

Molar mass of [tex]CaCO_3[/tex] = 100 g/mol

Putting values in equation 1, we get:

[tex]\text{Moles of }CaCO_3=\frac{80g}{100g/mol}=0.8mol[/tex]

For the given chemical reaction:

[tex]CaCO_3\rightarrow CaO+CO_2[/tex]

By stoichiometry of the reaction:

If 1 mole of [tex]CaCO_3[/tex] produces 1 mole of CaO

So, 0.8 moles of [tex]CaCO_3[/tex] will produce = [tex]\frac{1}{1}\times 0.8=0.8mol[/tex] of CaO

We know, molar mass of [tex]CaO[/tex] = 56 g/mol

Putting values in above equation, we get:

[tex]\text{Mass of CaO}=(0.8mol\times 56g/mol)=44.8g[/tex]

The percent yield of a reaction is calculated by using an equation:

[tex]\% \text{yield}=\frac{\text{Actual value}}{\text{Theoretical value}}\times 100[/tex] ......(2)

Given values:

Actual value of the product = 39 g

Theoretical value of the product = 44.8 g

Plugging values in equation 2:

[tex]\% \text{yield}=\frac{39 g}{44.8g}\times 100\\\\\% \text{yield}=87.05\%[/tex]

Hence, the % yield of the product is 87.05 %

In the reaction
Cu° + 2 H2SO4 → CuSO4 + 2 H2O + SO2,
copper is
A) reduced and is the oxidizing agent
B) reduced and is the reducing agent
C) oxidized and is the oxidizing agent
D) oxidized and is the reducing agent

Answers

Copper is D) oxidized and is the reducing agent

EXPLANATION: Copper goes from a charge of 0 in Cu to +2 in CuSO4 so it is oxidized. A reducing agent is the substance being oxidized.

What happens to the particle motion of a substance if the temperature changes?

Answers

Answer:

With an increase in temperature, the particles move faster as they gain kinetic energy, resulting in increased collision rates and an increased rate of diffusion. ... With an increase in temperature, the particles gain kinetic energy and vibrate faster and more strongly

Explanation:

Radhe Radhe

How does dissolving a salt molecule in water make its atoms ionize?

Answers

Answer:

It's take 1 and a half hours

Explanation:

Ugbdunvisrtg

Which one is it ?! (Hurry)

Answers

second one!!!!!!!!!!!!!!

A TV has a standby current of 0.05 amperes. The voltage going through the TV is 120 volts. Determine the power consumption while the TV is in standby.

Answers

Answer:

6 Watts

Explanation:

From the question given above, the following data were obtained:

Current (I) = 0.05 A

Voltage (V) = 120 V

Power (P) =?

Electrical power is defined by the following equation

The power consumption while the TV is in standby can be obtained as follow:

Power (P) = Current (I) × Voltage (V)

P = IV

With the above formula, we can obtain the power consumption while the TV is in standby. This can be obtained as follow:

Current (I) = 0.05 A

Voltage (V) = 120 V

Power (P) =?

P = IV

P = 0.05 × 120

P = 6 Watts

Therefore, the power consumption while the TV is in standby is 6 Watts.

SOMEONE HELP chemistry

Answers

Calculate the molar masses of H2O and CuSO4 (Relative atomic masses: H=1, O=16, S=32, Cu=64)

Calculate the mass of water driven off, and the mass of anhydrous copper(II) sulfate formed in your experiment

Calculate the number of moles of anhydrous copper(II) sulfate formed

Calculate the number of moles of water driven off

Calculate how many moles of water would have been driven off if 1 mole of anhydrous copper(II) sulfate had been formed

Write down the formula for hydrated copper(II) sulfate.

AMSWER IN THE ATTACHMENT.

which is an example of the force of attraction between two obects that have mass?

Answers

Answer:

gravity

Explanation:

Gravity is an example of the force of attraction between two objects that have mass.

Help me with this science question on the middle one..

Answers

Networks of feeding relationships is correct

What type of force are you exerting when you lie on a bed?
A. Electric force
B. Magnetic force
C. Compression
D. Tension

Answers

Answer:

C. Compression

Explanation:

I'm pretty sure it's compression

How much energy would be produced from the reaction of 2.40 moles hydrogen with 3.95 moles chlorine? ___ H2 + ___ Cl2 ___ HCl ΔH = -554 kJ

Answers

Answer:

How much energy would be produced from the reaction of 2.40 moles hydrogen with 3.95 moles chlorine?

[tex]H_2 + Cl_2 -> 2HCl , deltaH = -554 kJ[/tex]

Explanation:

Given,

2.40 moles hydrogen reacts with 3.95 moles chlorine.

From the balanced chemical equation,

1mol. of H2 reacts with 1mol. of Cl2

then,

2.40mol. of H2 reacts with ----?mol of Cl2

[tex]=>2.40 mol. H2 * \frac{1mol. Cl2}{1mol. H2} \\=2.40 mol. Cl2[/tex]

So, the remaining moles of Cl2 is in excess.

The limiting reagent is--- H2.

1mol. of H2 releases --- 554kJ of energy

then,

2.40mol of H2 releases ---- ?

[tex]=>2.40mol * \frac{554kJ}{1 mol.} \\=1329.6kJ[/tex]

Answer is: deltaH =-1329.6kJ

How many grams of HNO3 is needed to make 1.5 L of a 3 M solution of HNO3? Show work

Answers

Answer:

283.5g

Explanation:

first u need to know the molar mass of hno3 which is 63.01

the g=1.5×3×63.01

g= 283.5

Calculate the change in thermal energy when 2kg of water is heated from 20°C to 80°C.​

Answers

Answer:

504000 J

Explanation:

Applying,

Δq = cm(Δt)............. Equation 1

Where Δq = change in thermal energy, c = specific heat capacity of water,  m = mass of water, Δt = change in temperature.

From the question,

Given: m = 2 kg, Δt = 80-20 = 60°C

Constant; c = 4200 J/kg.°C

Substitute these values into equation 1

Δq = 2(4200)(60)

Δq = 504000 J

Hence the thermal energy is  504000 J

ChemBonding9. In ammonium chloride NH4Cl, the bonding between NH4+ and chloride ion Cl− is _______.
options:

ionic
polar covalent
nonpolar covalent

Answers

So NH4Cl has ionic bond between NH4+ and Cl-, hydrogen bond (can be considered covalent bond too and N and H are both non metals and covalent bonds occur between non metals) between N and H in NH4 and covalent bond between NH4 and another NH4.

i need help with this asap for brainly

Answers

Sodium does not make up these proteins.

3. Which best describes the definition for the atomic mass of an element?

A. It is a ratio based on the mass of the carbon-12 atom.

B. It is the sum of the protons. And neutrons in one atom of the element.

C. It is twice the number of protons in one atom of the element.

D. It is a weighted average of the masses of an element’s isotopes.

Answers

Answer:

B

Explanation:

Its the sum of the protons and neutrons.

name the gas which is formed when coal is heated in the absense of air​

Answers

Answer:

Coke

Explanation:

A solid fuel formed by heating coal in the absence of air is coke. Coke is black colored, tough porous substance. It is pure carbon.

An atom or ion has 42 neutrons
, 36 protons, and 36 electrons. Identify the element symbol, and determine the mass number and charge for this atom or ion

Answers

Answer:

Krypton

Explaination:

Element-Krypton

Symbol-Kr

Mass-83.8amu

charge-none

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In general, the more physical activity individuals do, __________.A.the more intense the exercise needs to beB.the more money they will save on dietingC.the more television they will be able to watchD.the more benefit they will receive from exercisePlease select the best answer from the choices provided.ABCD Which are characteristics of the US mixed market economy Select the interval where g is negative.PLSSS HELLPPP!!! Can someone check tell me why 1) is correct and why 2) is incorrect?! Willing to give brainliest 2. Do you think Princess has any reason to be jealous? Answer YES or NO and give reasons for your answer from the text of sophiatown A ship goes at the rate of (3m-2) knots per hour. How far can it travel in (4m+9) hours? Explain how the body prevents particles in inspired air from reaching the gasexchange surfaces. An investor, who had $75,000 to contribute, was choosing between a boutique and a local shoe shop. After careful deliberation, the investor chose the boutique. In the first year, the boutique generated enough profit to pay the investor $15,000 (an agreed percentage of profits to be paid to the investor). The investor found out that if he had invested in the local shoe shop he would have received $9,000 (an agreed percentage of profits to be paid to the investor).The investor's economic profit was:________ Your money will be refunded if the goods prove to be. ( satisfy) EXAMPLES OF PURE SUBSTANCES Find the missing segment in the image below help please asap please l The picture is above Ill mark as brainliest. A fitness club offers two membership plans. Plan A: $30 per month Plan B: $18 per month plus $2 for visit for each visit to the club a) graph the linear system. When would the cost of the two membership plans be the same B) describe a situation under which you would Choose each planHelp please Which argument relies primarily on an appeal to pathos, or emotion?A.Disease-resistance and high nutrient content often go hand-in-hand. By testing disease-resistant varieties for their nutritional content, we could find plants that would support the environment, consumers, and farm workers.B.We want to be nourished by sunshine, rain, and healthy soil, so sustainably grown food should be at the top of our shopping lists.C. When farmers grow crops, they remove nutrients from the soil. Without replenishment, land is depleted of nutrients and either becomes unusable or produces reduced yields. Sustainable agriculture replenishes the soil while minimizing the need for nonrenewable sources.D. Imagine a three-legged stool. What happens if one of the legs breaks? The whole stool falls over. This three-legged stool is a metaphor for the need to consider the economic, social, and environmental impacts of agriculture. If the system fails in any one of these areas, it can no longer support producers and contribute to the community in the long term. Which ordered pair is the best estimate for the solution of the system of equations?y=32x+6y=14x2(7, 3.5)(7, 4)(6.5, 3.5)(6, 3) 2097152 in exponential form who are maha-samanthas One source of aluminum metal is alumina, Al2O3. a. Determine the percentage composition of Al in alumina. b. How many pounds of aluminum can be extracted from 2.0 tons of alumina.? plss help me will give brainliest