Use the unbalanced chemical equation to answer the question.
2NaHCO3 → Na2CO3 + CO2
Which of the following can be added to the products to balance the equation?
(1 point)
Responses
H2
H 2
CH2OH
CH 2 OH
O2
O 2
H2O
H2O
Use the chemical equation to complete the activity.
2Cu+S→Cu2S
Copper (Cu) reacts with sulfur (S) to form copper sulfide as shown in the equation. A scientist adds 12.7 grams of Cu to 3.2 grams of S to start the reaction. In this reaction, all of the copper and all of the sulfur react. Before running the experiment, the scientist expected the products of the reaction will be a total of 15.9 grams of copper sulfide (Cu2S). In 1–2 sentences, explain the law that the scientist used to predict that the product of the reaction would be 15.9 grams of copper sulfide.
The scientist used the law of conservation of mass to predict that the product of the reaction would be 15.9 grams of copper sulfide. This law states that matter cannot be created or destroyed in a chemical reaction, so the total mass of the reactants must equal the total mass of the products.
To balance the equation, we need to make sure that the number of atoms of each element on both sides of the equation is equal.
Looking at the unbalanced equation:
2NaHCO3 → Na2CO3 + CO2
We can see that the number of sodium (Na) atoms is already balanced on both sides, with 2 on the left side and 2 on the right side.
However, we have 2 hydrogen (H) atoms on the left side (in NaHCO3) and 0 hydrogen atoms on the right side. We can fix this imbalance by adding H2O to the products side, which will provide the necessary hydrogen atoms.
So, the correct answer is H2O.
To balance the chemical equation, you need to ensure that the number of atoms on both sides of the equation is equal. In this case, we have:
2NaHCO3 → Na2CO3 + CO2
Currently, the number of sodium (Na), hydrogen (H), carbon (C), and oxygen (O) atoms are not equal on both sides. Let's analyze the equation step by step:
On the left side, we have:
- Sodium (Na): 2 atoms
- Hydrogen (H): 2 atoms (since there are 2 hydrogen atoms in each NaHCO3 molecule)
- Carbon (C): 1 atom (since there is only 1 carbon atom in NaHCO3)
- Oxygen (O): 5 atoms (2 from the carbonate group and 3 from the three oxygen atoms)
On the right side, we have:
- Sodium (Na): 2 atoms
- Carbon (C): 1 atom
- Oxygen (O): 3 atoms (only from the carbon dioxide molecule)
From this analysis, we can see that the number of hydrogen and oxygen atoms is unbalanced. In order to balance the equation, we need to add the appropriate coefficients to the reactants or products.
Looking at the given options, let's consider each one:
1. H2 (hydrogen gas): This will not balance the equation as it does not contribute to the unbalanced atoms.
2. CH2OH (methanol): This compound also does not contain any of the atoms that need balancing.
3. O2 (oxygen gas): Adding O2 to the products will increase the number of oxygen atoms, which is exactly what we need to balance the equation. Therefore, O2 can be added to balance the equation.
4. H2O (water): While adding water (H2O) will balance the hydrogen atoms, it will also introduce additional oxygen atoms, further unbalancing the equation.
In conclusion, the correct choice to balance the equation is O2. Adding O2 to the products will ensure that the number of oxygen atoms is balanced on both sides of the equation.