In an oxidation reaction, one species is oxidized (loses electrons). During a reduction reaction, one species is reduced (gains electrons). These transfers of electrons results in the change of oxidation states. One way to help you remember which reaction is which, is by using the mnemonic: OIL RIG - Oxidation Is Loss of electrons; Reduction Is Gain of electrons.

In an oxidation reaction, one species is oxidized (loses electrons). During a reduction reaction, one species is reduced (gains electrons). These transfers of electrons results in the change of oxidation states. One way to help you remember which reaction is which, is by using the mnemonic: OIL RIG - Oxidation Is Loss of electrons; Reduction Is Gain of electrons.

By looking at the reaction, we see that the cations for the reactants have their anions switched in the products. This means that the reaction follows the general outline:

This is an example of a double-replacement reaction.

Addition reactions convert two reactants to a single product, while decomposition reactions convert a single reactant to multiple products. Single-replacement reactions only switch one cation-anion pair.

The oxidizing agent is the element that causes the other element to be oxidized, and is itself being reduced in the equation. Reduction is defined as the gain of electrons, meaning the element would get "more negative."

In this reaction, aluminum transitions from an oxidation state of 3+ to an oxidation state of 0. This indicates a reduction, as the atom has gained more electrons and reduced charge. is thus the oxidizing agent in this reaction.

By looking at the reaction, we see that the cations for the reactants have their anions switched in the products. This means that the reaction follows the general outline:

This is an example of a double-replacement reaction.

Addition reactions convert two reactants to a single product, while decomposition reactions convert a single reactant to multiple products. Single-replacement reactions only switch one cation-anion pair.

The oxidizing agent is the element that causes the other element to be oxidized, and is itself being reduced in the equation. Reduction is defined as the gain of electrons, meaning the element would get "more negative."

In this reaction, aluminum transitions from an oxidation state of 3+ to an oxidation state of 0. This indicates a reduction, as the atom has gained more electrons and reduced charge. is thus the oxidizing agent in this reaction.

In a double displacement reaction, or double replacement reaction, opposite ions combine. What this means is that the cation of one compound will recombine and bond to the anion of the other compound and vice versa.

In this example, we have to remember the ideal convention of cations being written before the anion in the compound. So in AB, we can presume A being the cation and B being the anion. The same goes for CD - C is the cation and D is the anion.

With this in mind, we can now easily see how the replacement would be possible.

If A is a cation, and was originally bound to B (anion), the only other anion it is left with to bind is D. If C is a cation, and was originally bound to D (anion), it is only left with the option of binding to the now-free B anion.

That's why it is:

In a double displacement reaction, or double replacement reaction, opposite ions combine. What this means is that the cation of one compound will recombine and bond to the anion of the other compound and vice versa.

In this example, we have to remember the ideal convention of cations being written before the anion in the compound. So in AB, we can presume A being the cation and B being the anion. The same goes for CD - C is the cation and D is the anion.

With this in mind, we can now easily see how the replacement would be possible.

If A is a cation, and was originally bound to B (anion), the only other anion it is left with to bind is D. If C is a cation, and was originally bound to D (anion), it is only left with the option of binding to the now-free B anion.

That's why it is:

The process illustrated is the reduction of the chromium atom. Reduction occurs when electrons are gained, causing the oxidation number (charge) of the atom to decrease. We can examine this process by looking at the oxidations numbers of each atom involved.

Oxygen always has an oxidation number of , and the ion has a total charge of . This allows us to find the oxidation number for chromium. Note that there are two chromium atoms and seven oxygen atoms in the ion.

The initial oxidation state of chromium is .

Following the reaction, chromium has a charge of , meaning that it also has an oxidation number of .

During the process, the chromium atom went from an oxidation state of to an oxidation state of . This means that it must have gained electrons (reducing the oxidation state). This is a reduction process.

The process illustrated is the reduction of the chromium atom. Reduction occurs when electrons are gained, causing the oxidation number (charge) of the atom to decrease. We can examine this process by looking at the oxidations numbers of each atom involved.

Oxygen always has an oxidation number of , and the ion has a total charge of . This allows us to find the oxidation number for chromium. Note that there are two chromium atoms and seven oxygen atoms in the ion.

The initial oxidation state of chromium is .

Following the reaction, chromium has a charge of , meaning that it also has an oxidation number of .

During the process, the chromium atom went from an oxidation state of to an oxidation state of . This means that it must have gained electrons (reducing the oxidation state). This is a reduction process.