Suppose 2 grams of an unknown metal carbonate MCO3 is reacted with excess HCl and 0.88 grams of CO2 are produced. What is the atomic mass (molar mass) of the unknown metal M? What element is it?
MCO3 ==> MO + CO2
0.88g CO2 = how many mols CO2? That will be 0.88/44 = 0.02 mols.
The equation tells you that mols MCO3 = 0.02 also.
Then mol = grams/molar mass You know g and you know mol, calculate molar mass. Then You know MCO3 molar mass. You know C and O. solve for atomic mass M. Finally identify M from the periodic table.
To determine the atomic mass (molar mass) of the unknown metal M and identify the element, we need to use the law of conservation of mass.
1. Start by calculating the number of moles of CO2 produced:
Moles of CO2 = Mass of CO2 / Molar mass of CO2
Moles of CO2 = 0.88 g / 44.01 g/mol (molar mass of CO2)
Moles of CO2 = 0.02 mol
2. Since the balanced equation for the reaction involves one mole of MCO3 producing one mole of CO2, we can conclude that:
Moles of MCO3 = Moles of CO2 = 0.02 mol
3. The molar mass of MCO3 can be calculated using the formula weight method:
Molar mass of MCO3 = Mass of MCO3 / Moles of MCO3
Molar mass of MCO3 = 2 g / 0.02 mol
Molar mass of MCO3 = 100 g/mol
4. Breaking down the formula MCO3, we find that M represents the metal element. To identify the specific metal, we need to search for the most common potential metal elements that form carbonates.
Based on the periodic table, common metal elements that form carbonates include:
- Sodium (Na)
- Potassium (K)
- Calcium (Ca)
- Magnesium (Mg)
- Iron (Fe)
- Copper (Cu)
- Zinc (Zn)
You would need additional information or experimental data to determine the specific metal element M.
To determine the atomic mass (molar mass) and identify the unknown metal M, we can use the concept of stoichiometry and the balanced chemical equation for the reaction.
First, let's write the balanced chemical equation for the reaction:
MCO3 + 2HCl -> MCl2 + H2O + CO2
According to the equation, 1 mole of MCO3 reacts with 2 moles of HCl to produce 1 mole of CO2.
We are given that 2 grams of MCO3 produces 0.88 grams of CO2. To find the molar mass of MCO3 and subsequently the atomic mass of M, we need to follow these steps:
Step 1: Find the number of moles of CO2 produced.
We can use the molar mass of CO2 to find the number of moles:
Molar mass of CO2 = 12.01 g/mol (atomic mass of C) + (2 x 16.00 g/mol) (atomic mass of O)
Molar mass of CO2 = 44.01 g/mol
Number of moles of CO2 = Mass of CO2 / Molar mass of CO2
Number of moles of CO2 = 0.88 g / 44.01 g/mol
Number of moles of CO2 ≈ 0.02 mol
Step 2: Calculate the number of moles of MCO3.
According to the balanced equation, the ratio between moles of CO2 and moles of MCO3 is 1:1.
Therefore, the number of moles of MCO3 is also ≈ 0.02 mol.
Step 3: Find the molar mass of MCO3.
Molar mass of MCO3 = Mass of MCO3 / Number of moles of MCO3
Molar mass of MCO3 = 2 g / 0.02 mol
Molar mass of MCO3 = 100 g/mol
Step 4: Identify the element M.
To find the atomic mass (molar mass) and the element M, we need to refer to the periodic table. The molar mass of MCO3 is 100 g/mol, and this corresponds to the molar mass of the element M. By looking up the periodic table, we can identify the element with the nearest atomic mass of 100 g/mol, which is Calcium (Ca). Therefore, the unknown metal M is Calcium (Ca).
In summary, the atomic mass (molar mass) of the unknown metal M is 100 g/mol, and the metal is identified as Calcium (Ca).