Chemical Reactions Flashcards
Study Unit 1 Vocabulary
Matter
Anything that takes up space. Matter has mass and volume. States of matter: liquid, solid, gas
Observation
Information gathered by noticing what is going on through your senses (what you see, hear, smell, feel)
Property
Unique characteristics that help identify a substance and distinguish one substance from another Properties don’t change!
Qualitative
Data that is observable by your senses, no measurements, no instrumentation Think: quality!
Quantitative
Data that has a numeric value and uses measurements and instrumentation Think: quantity!
Substance
Is made up of only ONE type of material (atoms or molecules) all the way through
Mixture
Is made up of MORE THAN ONE substance (more than one type of atom or molecule)
Atom
The smallest piece of matter you can have that still has all the properties of that substance
Molecule
Matter made of 2 or more atoms bonded together
Solubility
The degree in which a substance dissolves in another substance (characteristic property)
Solvent
The liquid that is able to dissolve a substance (we used water and oil in activity 2.1)
Solute
The substance that is able to be dissolved in a liquid (in activity 2.1 we used baking soda, road salt, butter, soap, fat)
Melting Point
The temperature needed to make a substance’s particles change from the solid to the liquid phase (characteristic property)
Volume
The amount of space that a substance or object occupies
Mass
A measure of the amount of matter in an object (measured in grams)
Density
The ratio of mass to volume in a substance. A measure of how packed together the particles are (characteristic property)
Ratio
A proportion or relationship between two numbers
Chemical Reaction
A change that takes place when one or more substances (called reactants) form one or more new substances (called products) Reactant+reactant→ Products
Precipitate
A solid formed when two solutions react
Reactants
“Old stuff” AKA what you start with before the chemical reaction occurs. Reactants are BEFORE the arrow!
Products
“New stuff” AKA what you end the chemical reaction with. Products are AFTER the arrow!
Controlled Experiment
A fair test, an experiment where you can trust the data
Control Group
When running the experiment, this is the group you use for comparison
Acid Rain
Rain that has been made acidic by certain pollutants in the air
Scale Model
A copy of an object that is smaller or larger than the actual size of the object
Coefficient
A whole number placed in front of a chemical formula in an equation. It tells you the number of molecules or atoms of that substance in a chemical reaction
Subscript
A small number written below the symbol of an element in a chemical formula. It tells you how many atoms of that element are in a molecule: for example, in the formula “”, the “2” is a subscript letting you know that there are two hydrogen atoms in a water molecule.
Electrolysis
To break apart by electricity
Phase change
When matter changes from one state (solid, liquid, gas) to another
Closed System
A system or set-up that does not allow the transfer of matter in or out of the system (ex- alka seltzer in the bottle with the balloon covering the bottle preventing the gas from escaping)
Open System
A system or set-up that can exchange matter with its surroundings (ex- alka seltzer in the bottle without the balloon covering the bottle which allowed gas to escape)
Conservation of matter/mass
Matter cannot be created or destroyed. It can only change form.
