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
60 grams
60 grams
10 grams
The total mass of the products in the chemical reaction is 60 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 lost.
They are lost.
They gain mass.
They gain mass.
They are rearranged.
They are rearranged.
They maintain their properties.
During the reaction, the atoms of Fe and O2 are rearranged.
Which is most likely to occur during a chemical reaction?(1 point)
Responses
Atoms of the original substance are lost.
Atoms of the original substance are lost.
Mass is conserved.
Mass is conserved.
The original substance maintains its properties.
The original substance maintains its properties.
New atoms are created.
Mass is conserved during a chemical reaction.
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
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.
Some atoms gain mass after the reaction.
The correct statement about the reaction is: The atoms of the reactants are regrouped during the 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
4
4
8
8
2
2
5
There are four atoms of hydrogen (H) before the reaction. After the reaction, there are still four atoms of hydrogen.
To find the total mass of the products in the chemical reaction, you need to know the stoichiometry of the reaction. The stoichiometry tells you the ratios of reactants and products in terms of moles.
From the balanced chemical equation:
1 mole of CaCO3 yields 1 mole of CO2 and 1 mole of CaO.
Now, you need to determine the moles of CaCO3 in 30 grams. To do this, you need the molar mass of CaCO3, which is calculated by adding 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 (Ca) + 12.01 g/mol (C) + 3 * 16.00 g/mol (O) = 100.09 g/mol
Now, you can calculate the moles of CaCO3 by dividing the mass given (30 grams) by the molar mass of CaCO3:
30 g / 100.09 g/mol = 0.2997 mol (approximately)
Since the stoichiometry ratio is 1:1 for CaCO3 to CO2 and CaO, the moles of CO2 and CaO produced will also be approximately 0.2997 mol.
Finally, you can convert the moles of CO2 and CaO back to grams by multiplying the moles by their respective molar masses:
Molar mass of CO2:
12.01 g/mol (C) + 2 * 16.00 g/mol (O) = 44.01 g/mol
Mass of CO2:
0.2997 mol * 44.01 g/mol = 13.22 grams (approximately)
Molar mass of CaO:
40.08 g/mol (Ca) + 16.00 g/mol (O) = 56.08 g/mol
Mass of CaO:
0.2997 mol * 56.08 g/mol = 16.80 grams (approximately)
Therefore, the total mass of the products (CO2 and CaO) in the reaction is approximately 13.22 grams + 16.80 grams = 30.02 grams.