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
60 grams
60 grams
10 grams
10 grams
30 grams
30 grams
15 grams
The reaction shows that 1 mole of calcium carbonate (CaCO3) will yield 1 mole of carbon dioxide (CO2) and 1 mole of calcium oxide (CaO). To find the total mass of the products, we need to calculate the molar masses of each compound.
The molar mass of calcium carbonate (CaCO3) can be calculated by adding the atomic masses of its constituent elements:
Molar mass of CaCO3 = (1 mole of Ca x atomic mass of Ca) + (1 mole of C x atomic mass of C) + (3 moles of O x atomic mass of O)
The molar mass of carbon dioxide (CO2) can be calculated in a similar way:
Molar mass of CO2 = (1 mole of C x atomic mass of C) + (2 moles of O x atomic mass of O)
The molar mass of calcium oxide (CaO) can be calculated as follows:
Molar mass of CaO = (1 mole of Ca x atomic mass of Ca) + (1 mole of O x atomic mass of O)
By using the atomic masses from the periodic table, we can calculate the molar masses as follows:
Molar mass of CaCO3 = (1 x 40.08 g/mol) + (1 x 12.01 g/mol) + (3 x 16.00 g/mol) = 100.09 g/mol
Molar mass of CO2 = (1 x 12.01 g/mol) + (2 x 16.00 g/mol) = 44.01 g/mol
Molar mass of CaO = (1 x 40.08 g/mol) + (1 x 16.00 g/mol) = 56.08 g/mol
Now, using the molar mass values, we can calculate the mass of the products generated by 30 grams of calcium carbonate:
Mass of CO2 produced = (30 g CaCO3) x (1 mol CaCO3 / 100.09 g CaCO3) x (1 mol CO2 / 1 mol CaCO3) x (44.01 g CO2 / 1 mol CO2) = 13.19 g CO2
Mass of CaO produced = (30 g CaCO3) x (1 mol CaCO3 / 100.09 g CaCO3) x (1 mol CaO / 1 mol CaCO3) x (56.08 g CaO / 1 mol CaO) = 16.78 g CaO
Therefore, the total mass of the products is:
Mass of CO2 + Mass of CaO = 13.19 g + 16.78 g = 29.97 g
Rounded to two decimal places, the total mass of the products produced from 30 grams of calcium carbonate is 29.97 grams. Therefore, the closest answer is 30 grams.
no pick one of the responses
In that case, the closest answer is 30 grams.
Question
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 gain mass.
They gain mass.
They are lost.
They are lost.
They maintain their properties.
They maintain their properties.
They are rearranged.
The correct answer is "They are rearranged."
During the chemical reaction, the atoms of Fe (iron) and O2 (oxygen) are rearranged to form Fe2O3 (iron oxide). The reactants, Fe and O2, combine to form the product Fe2O3. The atoms themselves are not lost or gained, and they maintain their properties. However, their arrangement changes as they form the new compound.
Which is most likely to occur during a chemical reaction?(1 point)
Responses
New atoms are created.
New atoms are created.
The original substance maintains its properties.
The original substance maintains its properties.
Atoms of the original substance are lost.
Atoms of the original substance are lost.
Mass is conserved.
The correct answer is "Mass is conserved."
During a chemical reaction, mass is conserved, meaning that the total mass of the reactants equals the total mass of the products. Atoms are not created or destroyed in a chemical reaction, but rather rearranged to form new substances. Therefore, the total number of atoms before the reaction is the same as the total number of atoms after the reaction.
Question
Use the chemical reaction to answer the question.
NaHCO3+HC2H3O2→NaC2H3O2+H2O+CO2
A student mixes baking soda ( NaHCO3
) and acetic acid ( HC2H3O2
) to produce a chemical reaction shown. Which statement about the reaction is correct?
(1 point)
Responses
Some atoms gain mass after the reaction.
Some atoms gain mass after the reaction.
There are more H atoms after the reaction.
There are more H atoms after the reaction.
Atoms of Na are destroyed during the reaction.
Atoms of Na are destroyed during the reaction.
The atoms of the reactants are regrouped during the reaction.
The atoms of the reactants are regrouped during the reaction.
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The correct answer is "The atoms of the reactants are regrouped during the reaction."
In a chemical reaction, atoms are rearranged to form new substances. The reactants, NaHCO3 and HC2H3O2, undergo a rearrangement of their atoms to form the products NaC2H3O2, H2O, and CO2. The atoms themselves are not destroyed or gained mass, but rather they are regrouped to form different compounds. This statement accurately describes the process of a chemical reaction.
Use the chemical reaction to answer the question.
2H2+O2→2H2O
There are four atoms of hydrogen ( H
) before the reaction. How many atoms of hydrogen are present after the reaction?
(1 point)
Responses
8
8
5
5
4
4
2