1) Both carbon dioxide and water are pure substances. How are they similar to each other?

A. both substances have a set ratio of atoms that cannot be separated by physical means.

B. both substances have a set ratio of atoms that can be separated by physical means.

C. both substances have the same physical and chemical properties.

D. both substances have the same physical properties, but different chemical properties.

2) Felipe made a toy boat out of clay, but it kept sinking in water. He changed the boat's design by making it slightly wider than before. Why did Felipe's newly designed boat float on water?

A. He decreased the density by increasing the volume.

B. He decreased the density by decreasing the volume.

C. He increased the density by increasing the volume.

D. He increased the density by decreasing the volume.

My Answer is:

1~ C.) both substances have the same physical and chemical properties.

2~ C.) He increased the density by increasing the volume.

1. C CAN'T be right. Water is a liquid and CO2 is a gas so they don't have the same physical properties and you know they don't have the same chemical properties.

2. see below.

SO Sorry !

Cheeks

dcacbabcbbacbaa is not the answers I promise :(

1) I'm sorry, but your answer for question 1 is incorrect.

The correct answer is A. both substances have a set ratio of atoms that cannot be separated by physical means.

Both carbon dioxide (CO2) and water (H2O) are pure substances composed of molecules. In the case of carbon dioxide, it consists of one carbon atom bonded to two oxygen atoms, and in the case of water, it consists of two hydrogen atoms bonded to one oxygen atom. These atoms are chemically bonded, meaning they cannot be separated by physical means such as filtration or distillation. Therefore, both carbon dioxide and water have a fixed ratio of atoms that cannot be changed without a chemical reaction.

As for option C, while both substances do have similar physical properties like boiling points and melting points, they do have different chemical properties. Carbon dioxide is a gas at room temperature and is involved in processes like photosynthesis and respiration, while water is a liquid at room temperature and plays a crucial role as a solvent in many chemical reactions.

2) I'm sorry, but your answer for question 2 is also incorrect.

The correct answer is A. He decreased the density by increasing the volume.

When Felipe made the boat wider, he increased its volume while keeping the mass the same (assuming he didn't add more clay). Density is defined as mass divided by volume. By increasing the volume while keeping the mass constant, the overall density of the boat decreased. Since density is a measure of how compact an object is, a lower density means it is less likely to sink in a fluid like water. Therefore, the newly designed boat floated on water because its decreased density made it less dense than the water it displaced.