How much oxygen is needed to burn 3.00g of magnesium to form magnesium oxide? How can I illustrate in the Law of Conservation of Mass?
2Mg + O2 ==> 2MgO
mol Mg = g/atomic mass = 3.00 g/24.3 = 0.123
mols O2 required = (1/2)*0.123 = 0.0617
grams O2 = 0.0617 x 32 g = 1.97
Law conservation of mass says you don't gain or lose mass. So
Total MgO produced should be 3.00 + 1.97 = 4.97 g
NOTE: You can calculate how much MgO is produced. Since 1 mol Mg produces 1 mol MgO, then 0.123 mols MgO will be 0.1234 x 40.3 = 4.97 g MgO.
Well, oxygen is a real breath-taker when it comes to reactions! To burn 3.00g of magnesium and form magnesium oxide, you'd need 3.00g of oxygen. They make quite the fiery duo!
Now, let's talk about the Law of Conservation of Mass. It's like a "what goes in, must come out" rule for reactions. In this case, when you burn 3.00g of magnesium, it'll react with 3.00g of oxygen. That means the combined mass of magnesium and oxygen before the reaction is the same as the mass of magnesium oxide formed after the reaction. It's like a really nerdy magic trick - mass just can't disappear into thin air! So, the Law of Conservation of Mass is there to remind us that atoms are pretty good at following rules, even if they have a flare for chemical drama.
To determine the amount of oxygen needed to burn 3.00g of magnesium, we first need to understand the balanced chemical equation for the reaction.
The balanced equation for the combustion of magnesium can be represented as follows:
2Mg + O2 → 2MgO
According to this equation, 2 moles of magnesium react with 1 mole of oxygen gas to form 2 moles of magnesium oxide.
To calculate the amount of oxygen needed, we'll follow these steps:
Step 1: Determine the molar mass of magnesium.
The molar mass of magnesium (Mg) is approximately 24.31 g/mol.
Step 2: Convert the mass of magnesium to moles.
To convert grams of magnesium to moles, we divide the given mass (3.00g) by the molar mass (24.31 g/mol):
3.00g / 24.31 g/mol = 0.1234 mol
Step 3: Apply the stoichiometry of the balanced equation.
Since the equation shows that 2 moles of magnesium react with 1 mole of oxygen gas, we can conclude that for every 2 moles of Mg, we need 1 mole of O2.
Therefore, if we have 0.1234 moles of Mg, we would need 0.1234/2 = 0.0617 moles of O2.
Step 4: Convert moles of oxygen to grams.
To convert moles of oxygen to grams, we multiply the number of moles (0.0617 mol) by the molar mass of oxygen (which is approximately 32.00 g/mol):
0.0617 mol * 32.00 g/mol = 1.97g
Therefore, approximately 1.97 grams of oxygen is needed to burn 3.00 grams of magnesium to form magnesium oxide.
Now, let's see how this equation illustrates the Law of Conservation of Mass:
The Law of Conservation of Mass states that mass cannot be created or destroyed in a chemical reaction. It can only be rearranged or converted from one form to another.
In the given reaction equation:
2Mg + O2 → 2MgO
The total mass of the reactants (2 moles of Mg + 1 mole of O2) is equal to the total mass of the products (2 moles of MgO).
This shows that the mass of the reactants and products remains the same, adhering to the Law of Conservation of Mass. Therefore, the reaction illustrates the conservation of mass as no mass is gained or lost throughout the process.