Introduction to Chemistry

A&P Lecture 2

what is matter?

anything with mass that occupies space

what are the states of matter?

solid, liquid, and gas

what is chemistry?

the study of matter and its interactions

what are atoms?

the smallest unit of matter that retains its original elemental properties

what subatomic particles are atoms composed of?

protons, neutrons, and electrons

what are protons?

positively charged subatomic particles that are located in the nucleus

what is the nucleus?

an atoms central region

what are electrons?

negatively charged subatomic particles located in the electron shell

which subatomic particle is the smallest?

the electron

do the protons and neutrons in an atom have to be equal?

no

what is atomic mass calculated by?

the number of protons and neutrons

what is an atom mostly composed of?

empty space

what is the electron shell?

the area surrounding the nucleus where the electrons are found

how many electrons can the first electron shell hold?

2

how many electrons can the second electron shell hold?

8

how many electrons can the third electron shell hold?

18

what is the octet rule?

electron shells are stable with 8 electrons

what does the periodic table list?

elements by mass and properties

what elements are not present in the human body?

rare earth elements (57-71 and 89-92)

what are metals?

shiny substances that conduct electricity

what are non-metals?

gases or brittle solids that are poor conductors of electricity

what is the atomic number?

the number of protons in an atom

what is the atomic mass?

the number of protons + the number of neutrons

what are isotopes?

atoms with the same number of protons but different number of neutrons

do isotopes have a chemical property?

no

what is a mixture?

2 or more elements (atoms) physically mixed but not chemically changed

what are the 3 types of mixtures?

suspensions, colloids, and solutions

what is a suspension?

a liquid mixed with a solid where the particles are visible and settle out

what is a colloid?

appears opaque with tiny particles that do not settle out and are not visible

what is a solution?

composed of a solute and solvent with particles that dissolve and do not settle out

what is a solute?

the substance that dissolves

what is the most important solvent in the human body?

water

what does an increase in solute increase?

concentration

what type of mixture is cytosol?

a suspension

what type of mixture is blood?

a colloid

what type of mixture is glucose and water?

a solution

what is a solvent?

the substance the solute dissolves in