1answer.
Ask question
Login Signup
Ask question
All categories
  • English
  • Mathematics
  • Social Studies
  • Business
  • History
  • Health
  • Geography
  • Biology
  • Physics
  • Chemistry
  • Computers and Technology
  • Arts
  • World Languages
  • Spanish
  • French
  • German
  • Advanced Placement (AP)
  • SAT
  • Medicine
  • Law
  • Engineering
Alinara [238K]
3 years ago
7

Question 1(Multiple Choice Worth 4 points) (04.05 LC) What is the oxidation number of manganese in MnO41−? +3 +4 +7 +8 Question

2(Multiple Choice Worth 4 points) (04.05 LC) Which of the following reactions could be used to power a battery because of the transfer of electrons? Pb22+ + 2Br− → PbBr CaCl2 + 2NaOH → Ca(OH)2 + 2NaCl KOH + HCl → KCl + H2O Zn + Cu2+ → Zn2+ + Cu Question 3(Multiple Choice Worth 4 points) (04.05 MC) Read the following chemical equation: 2Al + 3Br2 → 2AlBr3 Which statement best identifies and describes the oxidizing agent in the reaction? Al is the oxidizing agent because its oxidation number increases. Al is the oxidizing agent because its oxidation number decreases. Br2 is the oxidizing agent because its oxidation number increases. Br2 is the oxidizing agent because its oxidation number decreases. Question 4(Multiple Choice Worth 4 points) (04.05 MC) In which of the following reactions is chlorine (Cl) oxidized? Br2 + 2Cl− → Cl2 + 2Br− Cl2 + 2e− → 2Cl− 2ClO3− + 12H+ → Cl2 + 6H2O 2Na + Cl2 → 2NaCl Question 5(Multiple Choice Worth 4 points) (04.05 MC) The diagram shows the setup of an experiment. A few observations of the experiment are listed in the table below the diagram. A beaker filled three-fourths with a liquid labeled colorless silver nitrate solution is shown. A small strip is shown inside the beaker. The strip is labeled copper strip. The title of the image is Experimental Setup. Experimental Observations Observation Description 1 Solution turned blue 2 Gray particles were deposited on the edge of the strip Which of the following is the correct explanation for one of the given observations? Observation 2 is a result of nitrate ions moving into the solution. Observation 1 is a result of copper ions moving into the solution. Observation 1 is a result of silver atoms losing one electron. Observation 2 is a result of silver ions losing one electron.
Chemistry
1 answer:
Elan Coil [88]3 years ago
3 0

1) Answer is: the oxidation number of manganese in MnO₄⁻ is +7.

Permanganate anion has negative charge 1-.

Oxygen (O) in permanganate anion has oxidation number -2.

x + 4 · (-2) = -1.

x - 8 = -1.

x = +7; oxidation nzmber of manganese.

Oxidation number shows the degree of oxidation of an atom in a chemical compound.

2) Answer is: Zn + Cu2+ → Zn2+ + Cu.

In this chemical reaction, there is transfer of electrons from zinc (Zn) to copper (Cu). Zinc change oxidation number from 0 to +2 (lost electrons) and copper change oxidation number from +2 to 0 (gain electrons).

Oxidation half reaction: Zn⁰ → Zn²⁺ + 2e⁻.

Reduction half reaction: Cu²⁺ + 2e⁻ → Cu⁰.

In other chemical reactions, there is no change of oxidation number of elements.

3) Answer is: Br2 is the oxidizing agent because its oxidation number decreases.

Balanced chemical reaction: 2Al + 3Br₂ → 2AlBr₃.

In this chemical reaction, aluminium change oxidation number from 0 to +3 (lose electrons) and bromine change oxidation number from 0 to -1 (gain electrons, reduced).

Oxidizing agent is a substance that has the ability to oxidize other substances, to cause them to lose electrons.

In oxido-reduction reaction, at least one element lose and one element gain electrons.

4) Answer is: Br2 + 2Cl− → Cl2 + 2Br⁻.

Oxidation is increase of oxidation number.

In this balanced chemical reaction, chlorine change oxidation number from -1 (Cl⁻) to oxidation number 0 (Cl₂).

Oxidation half reaction: 2Cl⁻ → Cl₂⁰ + 2e⁻.

Reduction half reaction: Br₂ + 2e⁻ → 2Br⁻.

In other chemical reactions, chlorine is reduced.

5) Answer is: Observation 1 is a result of copper ions moving into the solution.

The reactivity series is a series of metals from highest to lowest reactivity. Metal higher in the reactivity series will displace another.

Copper (Cu) is higher in activity series than silver (Ag), so copper lose electron and silver gain electrons.

Copper is oxidized (increase of oxidation number) and silver is reduced.

You might be interested in
Which of the following reactions is a neutralization reaction? A. ZnCl2(aq) + CaCrO4(aq) → ZnCrO4(s) + CaCl2(aq) B. HNO3(aq) + L
g100num [7]
Neutralization reaction means the reactants must be one acid and one alkali, and the product will be H2O and metal salt.

The only one satisfying this will be B
3 0
3 years ago
How many moles of copper are needed to react with sulfur to produce 0.25 moles Ol
Tems11 [23]

Answer:

                       0.50 moles of Cu

Explanation:

                    The balanced chemical equation for given synthetic reaction is,

                                          2 Cu + S → Cu₂S

According to balance chemical equation,

                  1 mole of Cu₂S is produced by  =  2 moles of Cu

So,

          0.25 moles of Cu₂S will be produced by  =  X moles of Cu

Solving for X,

                      X  =  0.25 mol × 2 mol /  1 mol

                      X  =  0.50 moles of Cu

Hence, as the molar ratio of Cu to Cu₂S is 2:1 hence, to produce 0.25 moles of Cu₂S we will need 0.50 moles of Cu.

6 0
3 years ago
Explain why food chains do not tend to exceed four links.
Softa [21]
Energy is "lost" at each trophic level when you go up the chain. <span> Typically there are fewer organisms at higher trophic levels.

Hope this helps!</span>
3 0
3 years ago
Sugar can be converted to carbon dioxide and water by burning in air or by metabolic reactions inside living cells. How are thes
rjkz [21]

Answer:

These reactions are similar because the process is similar and the products are carbon dioxide they are different because the substances are different to outgo these reactions

Explanation:

5 0
3 years ago
Neutrons of an Adam have ____ charges and are located ____ the nucleus.
lyudmila [28]
B) they have no charges and are inside an atom.*
7 0
3 years ago
Other questions:
  • What are sources of electricity? List as many as you can
    14·1 answer
  • How many moles of solid NaF would have to be added to 1.0 L of 0.115 M HF solution to achieve a buffer of pH 3.46? Assume there
    9·1 answer
  • Why is it significant that the color emitted from the hydrogen emission spectrum is not white?
    6·1 answer
  • What factors trigger the evolution of a species?
    10·2 answers
  • using the balanced equation below how many grams of lead(||) sulfate would be produced from the complete reaction of 23.6 g lead
    5·1 answer
  • 2 examples of when scientists used space probe technology to find out more about comets.
    11·1 answer
  • Which element is likely to be the best conductor of electricity?
    7·2 answers
  • Which has the strongest intermolecular forces​
    13·2 answers
  • Which element listed below is a nonmetal?
    9·2 answers
  • Middle school science help please. ill give brainliest
    5·2 answers
Add answer
Login
Not registered? Fast signup
Signup
Login Signup
Ask question!