The Structure of Matter
what is the third state of matter solid, liquid, __________.
gas
each horizontal row
period
a group of 2 or more atoms held together by forces called chemical bonds
molecule
a characteristic that can be observed or measured without changing the identity of a substance.
physical property
on the left hand side of a chemical reaction
reactants
the number of these is the atomic number
a. proton
each vertical column also called a chemical family
group
a substance that forms when 2 or more elements join chemically
compound
what is a characteristic of a substance that cannot be observed without changing the identity of the substance
chemical property
what is a substance on the right side of the chemical reaction
product
A student is investigating a sample of an element. The student observes that the element is solid, shiny, and can be bent into a new shape. The student is most like observing a. carbon b. hydrogen c. aluminum
c. aluminum
have a shiny luster, malleable, solid at room temperature (mercury is the exception), good conductors of heat and electricity.
metals
a group of chemical symbols and numbers that show the number of atoms of each element in a molecule.
chemical formula
alters the form or appearance of a substance without changing the identity of the substance
physical change
what is the number in front of a chemical formula to show how many atoms or molecules of that substance are involved in the reaction
coefficient
Which of the following is a chemical symbol representing an element? a. C b. CO c. CO2 2. H2O
a. C
all element in group 17 and 18 and some elements in 14, 15, and 16 , very dull appearance, brittle, most are gases or solids at room temperature ex. carbon hydrogen
non metals
what shows that the molecule contains multiple atoms of an element
subscript
what is it that occurs when substance combine to form one or more new substances with different properties
chemical change
what describes a chemical reaction using chemical formulas, subscripts, and coefficients
chemical equation
the sum of protons, neutrons, and electrons in the atom.
atomic mass
have characteristics of both metals and nonmetals, located along the step like area near the right side
metalloids
what is a solid made up of particles that are arranged in a regular, repeating pattern
crystal
the forces that hold atoms together in molecules, are broken, and reformed
chemical bonds
what is the law that states matter is neither created nor destroyed during a chemical change
law of conservation of mass