Use the chemical reaction to answer the question.
CaCO3→CO2+CaO
A scientist heats 30 grams of calcium carbonate (CaCO3
) in the chemical reaction shown. What is the total mass of the products?
(1 point)
Responses
15 grams
15 grams
30 grams
30 grams
10 grams
10 grams
60 grams
The total mass of the products can be determined by using the stoichiometry of the chemical reaction. According to the balanced equation, 1 mole of CaCO3 produces 1 mole of CO2 and 1 mole of CaO.
To find the molar mass of CaCO3, we add the atomic masses of calcium (Ca), carbon (C), and three oxygen (O) atoms:
Ca = 40.08 g/mol
C = 12.01 g/mol
O = 16.00 g/mol
Molar mass of CaCO3 = (40.08 g/mol) + (12.01 g/mol) + (16.00 g/mol x 3) = 100.09 g/mol
Given that 30 grams of CaCO3 is used, we can calculate the number of moles:
30 g / (100.09 g/mol) = 0.2998 mol
Since the stoichiometry of the reaction shows a 1:1 ratio between CaCO3 and the products CO2 and CaO, the number of moles of CO2 and CaO will also be 0.2998 mol.
To find the mass of the products, we multiply the number of moles by their respective molar masses:
Mass of CO2 = 0.2998 mol x (44.01 g/mol) = 13.20 g
Mass of CaO = 0.2998 mol x (56.08 g/mol) = 16.81 g
Therefore, the total mass of the products, CO2 and CaO, is:
13.20 g + 16.81 g = 29.01 g
Rounded to the nearest gram, the total mass of the products is 29 grams. Therefore, the correct answer is:
30 grams
Use the chemical reaction to answer the question.
4Fe+3O2→2Fe2O3
What happens to atoms of Fe and O2 during the reaction?
(1 point)
Responses
They are rearranged.
They are rearranged.
They are lost.
They are lost.
They gain mass.
They gain mass.
They maintain their properties.
Atoms of Fe and O2 are rearranged during the reaction. In the reactants, Fe is combined with O2 to form the product Fe2O3, where the atoms of Fe and O2 are rearranged to create a new compound. Therefore, the correct answer is:
They are rearranged.
Which is most likely to occur during a chemical reaction?(1 point)
Responses
New atoms are created.
New atoms are created.
Mass is conserved.
Mass is conserved.
Atoms of the original substance are lost.
Atoms of the original substance are lost.
The original substance maintains its properties.
Mass is conserved during a chemical reaction. According to the law of conservation of mass, the mass of the reactants in a chemical reaction is equal to the mass of the products. Therefore, the correct answer is:
Mass is conserved.
To determine the total mass of the products, we need to use the stoichiometry of the chemical reaction. From the balanced equation:
1 mole of CaCO3 produces 1 mole of CO2 and 1 mole of CaO.
The molar mass of CaCO3 is 40 g/mol (the sum of the atomic masses of calcium, carbon, and oxygen).
So, 40 grams of CaCO3 is equal to 1 mole of CaCO3.
Using this information, we can calculate the moles of CaCO3:
30 grams of CaCO3 * (1 mol / 40 grams of CaCO3) = 0.75 moles of CaCO3.
Since the stoichiometry is 1:1, we will have 0.75 moles of CO2 and 0.75 moles of CaO.
The molar mass of CO2 is 44 g/mol (the sum of the atomic masses of carbon and oxygen).
So the mass of CO2 would be: 0.75 moles of CO2 * 44 grams of CO2/mole = 33 grams of CO2.
The molar mass of CaO is 56 g/mol (the sum of the atomic masses of calcium and oxygen).
So the mass of CaO would be: 0.75 moles of CaO * 56 grams of CaO/mole = 42 grams of CaO.
Therefore, the total mass of the products (CO2 + CaO) is 33 grams + 42 grams = 75 grams.
The correct response is:
The total mass of the products is 75 grams.
To determine the total mass of the products in the given chemical reaction, we need to examine the stoichiometry of the reaction. The stoichiometry defines the molar ratios between reactants and products.
In the balanced chemical equation, 1 mole of calcium carbonate (CaCO3) decomposes to produce 1 mole of carbon dioxide (CO2) and 1 mole of calcium oxide (CaO).
First, we need to convert 30 grams of calcium carbonate (CaCO3) to moles. For this, we need to know the molar mass of calcium carbonate, which is calculated by adding up the atomic masses of each element in the compound.
The atomic mass of Calcium (Ca) = 40.08 g/mol
The atomic mass of Carbon (C) = 12.01 g/mol
The atomic mass of Oxygen (O) = 16.00 g/mol
Therefore, the molar mass of calcium carbonate (CaCO3) = (40.08 g/mol) + (12.01 g/mol) + (16.00 g/mol x 3) = 100.09 g/mol
Next, we can calculate the number of moles of calcium carbonate:
moles of CaCO3 = mass (in grams) / molar mass
moles of CaCO3 = 30 g / 100.09 g/mol
moles of CaCO3 = 0.2996 mol (rounded to four decimal places)
Now, according to the balanced equation, the ratio between moles of CaCO3 and moles of CO2 is 1:1. Therefore, the moles of CO2 produced is also 0.2996 mol.
Similarly, the moles of CaO produced will also be 0.2996 mol, as per the stoichiometry.
To find the mass of each product, we multiply the number of moles by their respective molar masses:
Mass of CO2 = moles of CO2 x molar mass of CO2 = 0.2996 mol x (12.01 g/mol + 16.00 g/mol) = 0.2996 mol x 28.01 g/mol = 8.40 grams (rounded to two decimal places)
Mass of CaO = moles of CaO x molar mass of CaO = 0.2996 mol x 56.08 g/mol = 16.80 grams (rounded to two decimal places)
Finally, we calculate the total mass of the products:
Total mass of the products = Mass of CO2 + Mass of CaO = 8.40 grams + 16.80 grams = 25.20 grams
Therefore, the total mass of the products in the given chemical reaction is 25.20 grams.