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A. How can you tell if an element has been oxidized or reduced in a reaction? (1 point)

1 -By comparing the oxidation states of the element in the reactants and products.
2 -By observing changes in color during the reaction.
3 -By measuring the change in temperature of the reaction.
4 -By counting the number of moles of the element in the reaction.

b. Determine oxidation states and answer the following questions about the reaction 2Li + 2H2O → 2LiOH + H2.

1 -Oxidation state of Li in reactant
2 -Oxidation state of H in reactant
3 -Oxidation state of O in reactant

What type of reaction is this?

1- Synthesis
2 -Decomposition
3 -Single Replacement
4 -Double Replacement

Is it also a redox reaction? If so, what was oxidized and what was reduced?

1 -Yes, Li was oxidized, and H was reduced.
2 -No, it is not a redox reaction.
3 -Yes, H was oxidized, and O was reduced.
4 -Yes, Li was reduced, and O was oxidized.

User Mehrtash
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1 Answer

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Final answer:

To determine if an element has been oxidized or reduced in a reaction, compare the oxidation states of the element in the reactants and products. For the reaction 2Li + 2H2O → 2LiOH + H2, Li is oxidized and H is reduced.

Step-by-step explanation:

In order to determine if an element has been oxidized or reduced in a reaction, you can compare the oxidation states of the element in the reactants and products. If the oxidation state of the element increases, it has been oxidized. If the oxidation state decreases, it has been reduced.

For the reaction 2Li + 2H2O → 2LiOH + H2, the oxidation states are as follows:

  • Oxidation state of Li in reactant: 0
  • Oxidation state of H in reactant: +1
  • Oxidation state of O in reactant: -2

The reaction is a synthesis reaction and it is also a redox reaction. In this reaction, Li is oxidized from an oxidation state of 0 to +1, and H is reduced from an oxidation state of +1 to 0.

User Adam Williams
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