Calculating the Amount of Magnesium Used

Oct 13, 2025 by wbrum.org 42 views

Magnesium burns in air to form magnesium oxide, a chemical reaction that is crucial in various industrial processes. The reaction is as follows:

2 Mg(s) + O2(g) → 2 MgO(s)

In this reaction, magnesium metal (Mg) reacts with oxygen gas (O2) to produce magnesium oxide (MgO). The reaction is highly exothermic, releasing a significant amount of heat energy.

Calculating the Amount of Magnesium Used

To calculate the amount of magnesium metal used to produce 8 g of magnesium oxide, we need to use the molar masses of magnesium and magnesium oxide. The molar mass of magnesium (Mg) is 24.31 g/mol, and the molar mass of magnesium oxide (MgO) is 40.31 g/mol.

First, let's calculate the number of moles of magnesium oxide produced:

moles MgO = mass MgO / molar mass MgO moles MgO = 8 g / 40.31 g/mol moles MgO = 0.198 mol

Since the reaction is a 1:1 ratio between magnesium and magnesium oxide, the number of moles of magnesium used is also 0.198 mol.

Next, we can calculate the mass of magnesium used:

mass Mg = moles Mg × molar mass Mg mass Mg = 0.198 mol × 24.31 g/mol mass Mg = 4.81 g

Therefore, 4.81 g of magnesium metal was used to produce 8 g of magnesium oxide.

In conclusion, the calculation of the amount of magnesium metal used to produce 8 g of magnesium oxide involves understanding the chemical reaction and using the molar masses of magnesium and magnesium oxide. By following the steps outlined above, we can determine that 4.81 g of magnesium metal was used in the reaction.

The molar mass of magnesium (Mg) is 24.31 g/mol.
The molar mass of magnesium oxide (MgO) is 40.31 g/mol.
The reaction is highly exothermic, releasing a significant amount of heat energy.
The reaction is a 1:1 ratio between magnesium and magnesium oxide.

[1] "Chemical Reactions and Equations." BBC Bitesize, BBC, www.bbc.co.uk/bitesize/articles/z9k9hyc.
[2] "Molar Mass." Chemistry LibreTexts, Libretexts, chem.libretexts.org/Bookshelves/General_Chemistry/Book%3A_General_Chemistry_(OpenStax)/09%3A_Moles_and_Molarity/9.04%3A_Molar_Mass.

Q: What is the chemical reaction between magnesium and oxygen?

A: The chemical reaction between magnesium and oxygen is as follows:

2 Mg(s) + O2(g) → 2 MgO(s)

This reaction is highly exothermic, releasing a significant amount of heat energy.

Q: What is the molar mass of magnesium (Mg)?

A: The molar mass of magnesium (Mg) is 24.31 g/mol.

Q: What is the molar mass of magnesium oxide (MgO)?

A: The molar mass of magnesium oxide (MgO) is 40.31 g/mol.

Q: How do I calculate the amount of magnesium used to produce a certain amount of magnesium oxide?

A: To calculate the amount of magnesium used, you need to follow these steps:

Calculate the number of moles of magnesium oxide produced using the formula: moles MgO = mass MgO / molar mass MgO
Since the reaction is a 1:1 ratio between magnesium and magnesium oxide, the number of moles of magnesium used is also equal to the number of moles of magnesium oxide produced.
Calculate the mass of magnesium used using the formula: mass Mg = moles Mg × molar mass Mg

Q: What is the significance of the molar masses of magnesium and magnesium oxide in this reaction?

A: The molar masses of magnesium and magnesium oxide are crucial in calculating the amount of magnesium used to produce a certain amount of magnesium oxide. By using the molar masses, you can determine the number of moles of magnesium used and subsequently calculate the mass of magnesium used.

Q: Is the reaction between magnesium and oxygen reversible?

A: No, the reaction between magnesium and oxygen is not reversible. Once magnesium reacts with oxygen to form magnesium oxide, the reaction cannot be reversed.

Q: What are some common applications of magnesium oxide?

A: Magnesium oxide has several common applications, including:

As an antacid to neutralize stomach acid
As a fire starter or fire extinguisher
As a component in the production of cement and concrete
As a filler in plastics and rubber

Q: Can magnesium oxide be used as a fertilizer?

A: Yes, magnesium oxide can be used as a fertilizer. It provides essential nutrients to plants, promoting healthy growth and development.

Q: Is magnesium oxide toxic?

A: Magnesium oxide is generally considered non-toxic and safe for use in various applications. However, it is essential to handle it with care and follow proper safety protocols when working with it.

Q: Can magnesium oxide be used in cosmetics and personal care products?

A: Yes, magnesium oxide can be used in cosmetics and personal care products, such as skin creams, lotions, and sunscreens. It provides several benefits, including:

Moisturizing and soothing the skin
Reducing inflammation and irritation
Providing UV protection

Q: Are there any potential health risks associated with magnesium oxide?

A: While magnesium oxide is generally considered safe, there are some potential health risks associated with its use. These include:

Gastrointestinal upset, such as diarrhea or stomach cramps
Interactions with certain medications, such as blood thinners or antibiotics
Allergic reactions or skin irritation in some individuals

It is essential to consult with a healthcare professional before using magnesium oxide, especially if you have any underlying medical conditions or are taking medications.