Question

chemical equations
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• read the assignment carefully and make sure you answer each part of the question or questions.
• after youve written your response, go back and read it again to make sure your thoughts are clear.

your assignment
the law of conservation of matter states that matter can be neither created nor destroyed. your friend shows you the following chemical equation:
caco₃ → cao + co₂
he says that because the oxygen atoms are split between two different molecules in the products, the equation does not support the law of conservation of matter. is your friend right? explain your answer. draw a model showing the number of each type of atom in the reactants and products. use your model to explain your answer. use the \insert image\ button to upload your model.

Explanation:

To determine if the friend is right, we analyze the number of each atom in reactants and products. For \( \ce{CaCO_3} \) (reactant): 1 Ca, 1 C, 3 O. For products \( \ce{CaO} \) and \( \ce{CO_2} \): Ca (1 in \( \ce{CaO} \)), C (1 in \( \ce{CO_2} \)), O (1 in \( \ce{CaO} \) + 2 in \( \ce{CO_2} \) = 3). So, the number of each atom (Ca, C, O) is conserved. Splitting oxygen between molecules doesn't violate the law; matter isn't created/destroyed. Thus, the friend is wrong. A model (e.g., particle diagram) would show 1 Ca, 1 C, 3 O on both sides.

Answer:

The friend is not right. The chemical equation \( \ce{CaCO_3
ightarrow CaO + CO_2} \) follows the law of conservation of matter. In the reactant (\( \ce{CaCO_3} \)), there is 1 Ca, 1 C, and 3 O atoms. In the products, \( \ce{CaO} \) has 1 Ca and 1 O, and \( \ce{CO_2} \) has 1 C and 2 O. Summing the product atoms: Ca (1), C (1), O (1 + 2 = 3), which matches the reactant. Splitting oxygen between molecules does not create or destroy matter, so the equation supports the law.