Question

1. if the alka seltzer was added to water in a closed container, would the mass of the container increase, decrease, or remain the same? use a particle diagram to help justify your answer. conclusions: construct a scientific argument that answers the focus question using the claim, evidence, reasoning format. be sure to use evidence from the lab and the new vocabulary “conservation of mass” in your argument. claim: ____ evidence: __ reasoning: ____

Explanation:

Claim:

When Alka - Seltzer is added to water in a closed container, the mass of the container and its contents remains the same.

Evidence:

1. The law of conservation of mass states that in a closed system, the total mass of reactants is equal to the total mass of products. Alka - Seltzer (a mixture of sodium bicarbonate, citric acid, etc.) and water are the reactants. When they react, products like carbon dioxide gas, sodium citrate, etc. are formed. Since the container is closed, no matter (like the carbon dioxide gas) can escape.
2. From a particle - level perspective, the atoms in the reactant particles (atoms in Alka - Seltzer and water molecules) are rearranged to form product particles. The number of each type of atom remains constant throughout the reaction. For example, the number of carbon atoms in the bicarbonate ions of Alka - Seltzer will be equal to the number of carbon atoms in the carbon dioxide and other carbon - containing products.

Reasoning:

The law of conservation of mass applies to closed systems. In a closed container, there is no exchange of matter with the surroundings. The chemical reaction between Alka - Seltzer and water involves the rearrangement of atoms. The total number of atoms of each element before the reaction (in Alka - Seltzer and water) is equal to the total number of atoms of each element after the reaction (in the products). Since mass is related to the number and type of atoms (mass of an atom is constant), the total mass of the system (container + Alka - Seltzer + water) before the reaction is equal to the total mass after the reaction. So, the mass of the container and its contents remains unchanged.

Answer:

Claim:

When Alka - Seltzer is added to water in a closed container, the mass of the container and its contents remains the same.

Evidence:

1. The law of conservation of mass states that in a closed system, the total mass of reactants is equal to the total mass of products. Alka - Seltzer (a mixture of sodium bicarbonate, citric acid, etc.) and water are the reactants. When they react, products like carbon dioxide gas, sodium citrate, etc. are formed. Since the container is closed, no matter (like the carbon dioxide gas) can escape.
2. From a particle - level perspective, the atoms in the reactant particles (atoms in Alka - Seltzer and water molecules) are rearranged to form product particles. The number of each type of atom remains constant throughout the reaction. For example, the number of carbon atoms in the bicarbonate ions of Alka - Seltzer will be equal to the number of carbon atoms in the carbon dioxide and other carbon - containing products.

Reasoning:

The law of conservation of mass applies to closed systems. In a closed container, there is no exchange of matter with the surroundings. The chemical reaction between Alka - Seltzer and water involves the rearrangement of atoms. The total number of atoms of each element before the reaction (in Alka - Seltzer and water) is equal to the total number of atoms of each element after the reaction (in the products). Since mass is related to the number and type of atoms (mass of an atom is constant), the total mass of the system (container + Alka - Seltzer + water) before the reaction is equal to the total mass after the reaction. So, the mass of the container and its contents remains unchanged.