When 1.5 grams of magnesium burns, how many grams of magnesium oxide will be formed?
a) Write a balanced chemical equation for the above reaction.
b) Show by unit conversion (show conversion factors, ie. 2 g H20 x 1 mole H2O/18 g H2O x ...... x ...... = answer
2Mg + O2 ==> 2MgO
mols Mg = g/molar mass = ?
Use the coefficients in the balanced equation to convert mols Mg to mols MgO.
? mol Mg x (2 mol MgO/2 mol Mg) = ? mol Mg x (2/2) = x mol MgO.
g MgO = mols MgO x molar mass MgO.
a) To write a balanced chemical equation for the reaction where magnesium burns to form magnesium oxide, we need the chemical formulas for magnesium and magnesium oxide. The chemical formula for magnesium is Mg, and the chemical formula for magnesium oxide is MgO.
The balanced chemical equation for this reaction is:
2 Mg + O2 -> 2 MgO
This equation shows that 2 moles of magnesium combine with 1 mole of oxygen gas to produce 2 moles of magnesium oxide.
b) To determine the number of grams of magnesium oxide formed when 1.5 grams of magnesium burns, we can use unit conversion.
Given:
Mass of magnesium = 1.5 grams
To convert grams of magnesium to moles, we need to know the molar mass of magnesium (Mg). The molar mass of an element is the atomic mass in grams per mole. The atomic mass of magnesium is approximately 24.31 grams per mole.
Conversion factor:
1 mole Mg / 24.31 grams Mg
By multiplying the given mass of magnesium by this conversion factor, we can find the number of moles of magnesium:
1.5 grams Mg * (1 mole Mg / 24.31 grams Mg) = 0.0617 moles Mg
Now, using the balanced chemical equation, we know that 2 moles of magnesium react to form 2 moles of magnesium oxide.
Conversion factor:
2 moles MgO / 2 moles Mg
By multiplying the number of moles of magnesium by this conversion factor, we can find the number of moles of magnesium oxide:
0.0617 moles Mg * (2 moles MgO / 2 moles Mg) = 0.0617 moles MgO
Finally, to convert moles of magnesium oxide to grams, we need to know the molar mass of magnesium oxide (MgO). The molar mass of magnesium oxide is approximately 40.31 grams per mole.
Conversion factor:
40.31 grams MgO / 1 mole MgO
By multiplying the number of moles of magnesium oxide by this conversion factor, we can find the mass of magnesium oxide:
0.0617 moles MgO * (40.31 grams MgO / 1 mole MgO) = 2.48 grams MgO
Therefore, when 1.5 grams of magnesium burns, approximately 2.48 grams of magnesium oxide will be formed.
a) The balanced chemical equation for the reaction between magnesium and oxygen to form magnesium oxide can be written as:
2 Mg + O2 -> 2 MgO
b) To determine the number of grams of magnesium oxide that will be formed when 1.5 grams of magnesium burns, we need to use conversion factors to calculate the amount of magnesium oxide produced.
Step 1: Start with the given amount of magnesium (1.5 grams).
1.5 g Mg
Step 2: Use the molar mass of magnesium to convert grams to moles.
1 mole Mg = 24.31 grams Mg
1.5 g Mg x (1 mole Mg / 24.31 g Mg) = 0.062 moles Mg
Step 3: Use the balanced chemical equation to relate moles of magnesium to moles of magnesium oxide.
From the balanced equation: 2 moles Mg = 2 moles MgO
0.062 moles Mg x (2 moles MgO / 2 moles Mg) = 0.062 moles MgO
Step 4: Use the molar mass of magnesium oxide to convert moles to grams.
1 mole MgO = 40.31 grams MgO
0.062 moles MgO x (40.31 g MgO / 1 mole MgO) = 2.497 grams MgO (rounded to three decimal places)
Therefore, when 1.5 grams of magnesium burns, approximately 2.497 grams of magnesium oxide will be formed.