Happened to the Solid?
What happens when a solid dissolves?
The solid breaks into tiny pieces and mixes with the water.
What tests can you perform on a gaseous substance?
You can test for properties like density and flammability.
What is solubility?
Solubility is how well a substance dissolves in a liquid.
What is a chemical reaction?
A process where substances change into new substances.
What is a physical change?
A physical change is a change that affects one or more physical properties of a substance without altering its chemical composition.
What does mass conservation mean?
The total mass stays the same, even when substances change form.
What does a chemical formula represent?
A chemical formula shows the types and numbers of atoms in a molecule or compound.
What does density measure?
Density measures how much mass is contained in a given volume.
What happens to atoms in a chemical reaction?
Atoms break apart and rearrange to form new molecules.
What is a chemical change?
A chemical change results in the formation of new substances with different properties from the original substances.
How does temperature show melting vs. dissolving?
A temperature drop means dissolving, not melting.
How does mass change in an open system?
Mass may decrease if matter escapes or increase if matter enters the system.
How does color indicate a chemical change?
A change in color can suggest that a new substance has formed.
What are reactants and products?
Reactants are substances that undergo change, and products are what is formed as a result.
How can you tell if a change is physical or chemical?
If the change can be reversed and the original substance is still present, it is a physical change. If new substances are formed, it is a chemical change.
What is the difference between melting and dissolving?
Melting turns a solid into a liquid; dissolving mixes a solid with a liquid.
How do you identify the elements in a formula?
Elements are identified by their chemical symbols, which are usually one or two letters (e.g., H for hydrogen, O for oxygen).
How do properties help identify substances?
Properties like melting point help us tell substances apart.
What does it mean that matter is conserved?
The total mass before and after a reaction is the same.
Why might gas be confused with boiling?
Boiling also creates bubbles, which can look like gas production.
How can we tell if a solid dissolved in a liquid?
We can see that the solid disappears and the mixture becomes clearer, indicating it has dissolved.
How are molecules and compounds different?
All compounds are molecules, but not all molecules are compounds; molecules can consist of the same type of atoms (e.g., O2), while compounds consist of different types of atoms (e.g., H2O).
What happens to atoms in a reaction?
Atoms rearrange to form different molecules during a chemical reaction.
How do particles change during a reaction?
Particles break apart and rearrange to form new substances.
What happens to the properties of substances during a chemical change?
The properties of substances change because new substances are formed with different chemical and physical properties.