Chapter 1 Matter And Classification Flashcards
What is matter?
Matter can be regarded as anything that occupies space and has mass.
Matter is a fundamental concept in physics and chemistry, encompassing all physical substances.
What is a substance?
A substance is a form of matter that has a constant composition and distinct properties.
Substances can be elements or compounds.
List some properties of substances.
- Strength
- Thermal conductivity
- Electrical conductivity
- Magnetic ability
- Waterproofness
- Brittleness
- Malleability
- Ductility
These properties help in identifying and classifying different substances.
What is heat?
Energy in transit; spontaneous energy transfer from a hotter object to a colder object
Heat is a form of energy that flows due to a temperature difference.
What is a thermal conductor?
A material that is a good conductor of heat
Examples include most metals and diamond.
What is a thermal insulator?
A material that is a poor conductor of heat
Examples include air, ceramics, wood, and polystyrene.
Fill in the blank: Heat is the _______ from a hotter object to a colder object.
energy transfer
True or False: Diamond is a thermal insulator.
False
Diamond is classified as a thermal conductor.
List three examples of thermal insulators.
- Air
- Ceramics
- Wood
Fill in the blank: A good thermal conductor is typically a _______.
metal
What is an electrical conductor?
A material that is a good conductor of electricity
Examples include copper, water, graphite, and ions in solution.
What is an electrical insulator?
A material that does not conduct electricity
Examples include most non-metals and diamond.
Define brittle substances.
A material that breaks easily when a force is applied
Examples include pencil lead, glass, and ionic solids.
Fill in the blank: A _______ is a material that is a good conductor of electricity.
[electrical conductor]
True or False: Metals are typically good electrical insulators.
False
List three examples of brittle substances.
- Pencil lead
- Glass
- Ionic solids
What is a ductile substance?
A material that can easily be stretched or drawn out without breaking.
Most metals are ductile, such as copper wire.
What is an example of a ductile substance?
Copper wire
Copper is commonly used due to its ductility.
What is a malleable substance?
A material that is easily shaped or formed through hammering or high pressure processes.
Malleability is a key property of many metals.
What is an example of a malleable substance?
Modeling clay
Modeling clay is often used in arts and crafts due to its malleability.
True or False: Most metals are both ductile and malleable.
True
Most metals exhibit both properties, allowing them to be shaped and stretched.
Fill in the blank: A material that can be easily shaped or framed through hammering processes is called _______.
[malleable substance]
Fill in the blank: A material that can be stretched into wire is called _______.
[ductile substance]
What is the primary method for classifying matter?
By physical and chemical separation
What are the two main categories of matter?
Mixtures and pure substances
Define homogeneous mixtures
Mixtures with a uniform composition throughout
Define heterogeneous mixtures
Mixtures with a non-uniform composition
What type of matter is formed by chemical separation?
Compounds
What are elements?
Pure substances that cannot be broken down into simpler substances
Fill in the blank: __________ are substances that contain carbon and are typically found in living organisms.
Organic
Fill in the blank: __________ are substances that do not primarily contain carbon.
Inorganic
What are the three categories of elements based on their properties?
Metals, semi-metals, non-metals
What is a mixture?
A mixture consists of two or more substances.
Do the substances in a mixture retain their individual properties?
Yes, the substances retain their individual properties.
Can the components of a mixture be separated?
Yes, the components can be separated by physical means.
Are the substances in a mixture chemically bonded?
No, substances in a mixture are not chemically bonded to one another.
What are the two main classes of mixtures?
Mixtures can be classed as homogeneous or heterogeneous.
What is a homogeneous mixture?
The composition of homogeneous mixtures is constant throughout.
What is another name for homogeneous mixtures?
Homogeneous mixtures are also known as solutions.
In a solution, what is the substance present in the largest amount called?
The substance present in the largest amount is the solvent.
In a solution, what is the substance present in the smaller amount called?
The substance present in the smaller amount is the solute.
What characterizes heterogeneous mixtures?
Non-uniform compositions
Heterogeneous mixtures consist of components that are not evenly distributed.
Do the constituent substances in heterogeneous mixtures dissolve in each other?
No
The substances in heterogeneous mixtures maintain their individual properties and do not form a single phase.
What is a suspension?
A solid mixed with a liquid
In a suspension, the solid does not dissolve and can be separated by filtration.
Give an example of a suspension.
Solid cement in water (cement slurry)
This illustrates how solid particles are suspended in a liquid medium.
What are two liquids that mix completely called?
Miscible
Example: alcohol in water
What term describes liquids that do not mix?
Immiscible
Example: petrol in water
What type of solution do immiscible liquids form?
Heterogeneous solution
How can immiscible liquids be separated?
Using a separating funnel
What forms when two immiscible liquids are shaken?
Emulsion
Example: olive oil in balsamic vinegar
What is an example of recovering salt from brine?
Heating the solution to evaporate water
What method can be used to separate iron filings from sand?
Using a magnet
What is the characteristic of sand in relation to magnetism?
Non-magnetic
What method is used to separate oxygen and nitrogen in air?
Fractional distillation
Fill in the blank: Two liquids that mix completely are _______.
Miscible
Fill in the blank: Liquids that do not mix are _______.
Immiscible
True or False: An emulsion is formed by mixing two miscible liquids.
False
What is the appearance of an emulsion?
Milky-looking liquid
What are pure substances?
Pure substances consist of one type of substance only and are either elements or compounds.
What are elements?
Elements are the simplest pure substances that cannot be broken down into simpler substances through chemical means.
What are atoms?
Atoms are the building blocks of matter and the smallest particle that retains the properties of an element.
Give an example of an element.
Oxygen.
What are diatomic molecules?
Diatomic molecules are molecules composed of two atoms, which can be of the same or different elements.
List the diatomic molecules.
- H2
- N2
- F2
- O2
- I2
- Cl2
- Br2
A mnemonic for remembering diatomic molecules is ‘Have no fear of ice cold beer.’
What is a compound?
A compound is a pure substance comprised of two or more elements bonded together through chemical means.
What is the significance of fixed chemical composition in compounds?
Compounds have a fixed chemical composition where substances are bonded in a constant ratio.
Give an example of a compound.
Water (H2O).
What elements make up water?
- Hydrogen
- Oxygen
In water (H2O), what is the fixed ratio of hydrogen to oxygen?
There are always two hydrogen atoms for every one oxygen atom.
What does the fixed ratio of elements in compounds provide evidence for?
The fixed ratio of elements in compounds provides strong evidence for the atomic model.
What are compounds formed through?
Chemical processes
Compounds are substances made up of two or more elements that are chemically bonded together.
What is the only way to separate compounds into their constituent elements?
Chemical processes
Physical processes cannot separate compounds into their elements.
What does a chemical reaction involve?
Breaking and creation of chemical bonds
This process leads to the transformation of reactants into products.
Fill in the blank: Water can be separated into hydrogen and oxygen through _______.
Electrolysis
Electrolysis is a method that uses electrical energy to drive a chemical reaction.
What is the symbol for nitrogen?
N
The symbol for nitrogen is capitalized as it consists of one letter.
How is a two-letter element symbol formatted?
The first letter is capitalized and the second letter is lowercase.
Example: The symbol for cobalt is Co.
What is a compound?
A substance comprised of two or more elements.
Compounds are formed by the combination of different elements.
What information does the formula of a compound provide?
- Which elements are the constituents
- The ratio of atoms of each component element in the compound
This includes the number of atoms per molecule.
What is the chemical formula for carbon dioxide?
CO2
Carbon dioxide consists of 1 carbon atom and 2 oxygen atoms.
How many hydrogen atoms are in a water molecule?
2
A water molecule (H2O) contains 2 hydrogen atoms and 1 oxygen atom.
What is the chemical formula for calcium oxide?
CaO
Calcium oxide consists of 1 calcium atom and 1 oxygen atom.
True or False: The symbol for an element is always derived from its English name.
False
Some symbols are derived from the element’s Latin name, making them harder to remember.
Fill in the blank: The symbol for cobalt is ______.
Co
Cobalt’s symbol follows the two-letter format with the first letter capitalized and the second letter lowercase.
