chapter 3 (diversity of matter by chemical composition) secondary 1 Flashcards
What are elements?
Elements are the basic building blocks of every living and non-living thing.
Can elements be broken down into simpler substances?
No.
What are compounds?
Compounds are two or more elements that are CHEMICALLY combined together.
Can compounds be separated?
Yes, under chemical means. They are usually hard to separate.
What are mixtures?
Mixtures are made of two or more ELEMENTS or COMPOUNDS that are NOT CHEMICALLY COMBINED.
Can mixtures be separated?
Yes. They can be separated easily.
What different types of mixtures are there?
- Elements only
- Compounds only
- Both elements and compounds
What are the properties of mixtures?
Mixtures have the same characteristics of its constituents. (what makes the mixture)
ex. common salt is salty. when mixed with water, it forms a mixture. when tasting this mixture, it tastes salty as the salt dissolves in the water
Do the constituents of mixtures need to have a fixed proportion?
No.
What is a solution?
A solution is a mixture in which one substance completely dissolves in another.
What is a solute?
A solute is the substance that dissolves in a solution.
What is a solvent?
A solvent is the substance that dissolves another substance in a solution.
What is a dilute solution?
A solution that has a low percentage of dissolved solute.
What is a concentrated solution?
A solution in which there is a high percentage of dissolved solute.
What factors affects the rate of dissolving?
- The size of solute particles
- Temperature of the solvent
- Rate of stirring
- Nature of the solvent (change nature of solvent to the same as the solute)
What is a suspension?
A suspension is a mixture with insoluble substances in a solvent.
What are the characteristics of a suspension?
- Light cannot pass through fully
- Insoluble substances settle to form solid deposits
- Insoluble substances can be seen
What are the characteristics of a solution?
- Light can pass through fully
- No solid deposits of the solute
- Particles of the solute cannot be seen
What are the properties of a compound?
They do NOT have the same properties as their constituent elements.
What are homogenous substances?
Homogenous substances are substances with particles that are distributed non-uniformly. (not the same.)
What are heterogenous substances?
Substances with particles distributed uniformly.
Define solubility.
Solubility is the ability of a substance to dissolve in another without leaving remains.
