Exam 1 - Chapter 2A Flashcards
What do chemical elements do?
Compose all forms of matter
What is matter?
Matter is anything that has mass and takes up space; solid, liquid, or gas
What is the chemical make up of our body?
(1) 96% - major elements: carbon, hydrogen, oxygen, & nitrogen (2) 3.6% - lesser elements (3) .4% - trace elements
What are atoms, molecules, and compounds?
(1) atoms - smallest unit of matter that retains properties and characteristics of an element (2) molecule - 2 or more atoms sharing electrons (3) compound - a substance that can be broken down into 2 or more different elements
What are the subatomic particles?
Neutrons, protons, & electrons
(1) Atomic number - number of protons (2) Mass number - number of protons and neutrons
What is an ion?
An atom that has lost or gained an electron
What is a chemical bond?
Occurs when atoms are held together by forces of attraction
What is an ionic bond?
2 elements making the compound neutral
What is a covalent bond?
Two or more atoms share electrons; single, double, or triple
What is a polar covalent bond?
Covalent bond with +/- regions
What is a hydrogen bond?
2 other atoms associate with a hydrogen atom
What is hydrophilic and hydrophobic?
(1) hydrophilic - polar molecules, water loving (2) hydrophobic - non polar molecules, fears water
What is energy?
Capacity to do work; (1) potential - energy stored (2) kinetic - energy in motion (3) chemical - PE stores in bonds
What is a chemical reaction?
Occurs when new bonds form or old bonds break
What is a synthesis reaction?
A+B =AB (put together) -H2O
