Law of Conservation of Matter Quick Check
Science 8 Q1 / Matter Interactions
Suppose 10 atoms of carbon (C) react with 20 atoms of oxygen (O) to form 10 molecules of carbon dioxide (CO2
). According to the law of conservation of matter, how many atoms are present in this reaction?(1 point)
Responses
10
20
15
30
The correct answer is 30.
To find the number of atoms present in the reaction, we need to first determine the number of atoms in each molecule of carbon dioxide (CO2).
In one molecule of carbon dioxide (CO2), there is one atom of carbon (C) and two atoms of oxygen (O). So, a single molecule of CO2 contains a total of 3 atoms (1 C atom + 2 O atoms).
Since we have 10 molecules of CO2, we can multiply the number of molecules by the number of atoms in each molecule to find the total number of atoms.
10 molecules of CO2 x 3 atoms/molecule = 30 atoms
Therefore, according to the law of conservation of matter, there are 30 atoms present in this reaction.
So, the correct answer is 30.
According to the law of conservation of matter, the total number of atoms before and after a chemical reaction must remain the same. In this reaction, we start with 10 atoms of carbon and 20 atoms of oxygen. To form 10 molecules of carbon dioxide (CO2), we would need 10 atoms of carbon and 20 atoms of oxygen.
Therefore, the total number of atoms present in this reaction is 10 (atoms of carbon) + 20 (atoms of oxygen) = 30 atoms.
So the correct answer is 30.