1.
What is always true according to the Law of Conservation of Matter?
The total number of molecules before and after a chemical reaction stays the same.
Atoms can be rearranged during a chemical reaction but cannot be added or taken away.
New molecules cannot be formed from the reactants during a chemical reaction.
Atoms created during a chemical reaction must have the same mass as the atoms in the reactants.
Apologies for any confusion. The correct answer is:
Atoms can be rearranged during a chemical reaction but cannot be added or taken away.
You're welcome! I'm glad I could help. Yes, the correct explanation for why the student's claim is incorrect is that the reaction produced a gas that escaped the beaker, thus accounting for the discrepancy in mass. Well done on answering all the questions correctly!
All of the above statements are true according to the Law of Conservation of Matter.
are you sure?
1.
What is always true according to the Law of Conservation of Matter?
The total number of molecules before and after a chemical reaction stays the same.
Atoms can be rearranged during a chemical reaction but cannot be added or taken away. ☑️
New molecules cannot be formed from the reactants during a chemical reaction.
Atoms created during a chemical reaction must have the same mass as the atoms in the reactants.
2.
Using a physical change, what type of evidence would support the Law of Conservation of Matter?
The mass before the change occurred is less than the mass after the change.
The mass before the change is greater than the mass after the change.
The mass before the change occurred is the same as the mass after the change. ☑️
3.
Which procedure could be used to demonstrate that matter is conserved during a chemical change or reaction?
Find the mass of a stick of butter. Heat the butter until it melts. Find the mass of the melted butter.
Find the mass of a piece of paper. Tear the paper into smaller pieces. Find the mass of the pieces.
Find the mass of an acid and a base. Combine them to produce water and a salt. Find the mass of the water and salt. ☑️
Find the mass of a log. Burn the log until it turns to ash and smoke. Find the mass of the ash.
4.
A student combines two liquids in a beaker. She observes that the mass of the combined liquid is less than the mass of the two separate liquids. The student claims that this observation shows that matter is not conserved in chemical reactions. Which statement explains why the student's claim is incorrect?
The reaction produced a gas that escaped the beaker. ☑️
The reaction did not change the physical properties of the liquids.
The product contained fewer atoms than the reactants.
The combined liquid was warmer than the two separate liquids.
4/4 correct ( also thanks bot too! :D )
The correct answer is:
Atoms can be rearranged during a chemical reaction but cannot be added or taken away.
The Law of Conservation of Matter states that matter cannot be created or destroyed in a chemical reaction. This means that the total number of atoms before the reaction must equal the total number of atoms after the reaction. However, atoms can definitely be rearranged to form new molecules during the reaction. So, while the arrangement of atoms may change, the total number of atoms remains constant. Therefore, the statement that "Atoms can be rearranged during a chemical reaction but cannot be added or taken away" is always true according to the Law of Conservation of Matter.