Biology I-Chapter 2-1 (MLHS)

atom

basic unit of matter; the smallest part of an element

chemical formula

abbreviation for a compound

radioactive

describes an isotope in which the nucleus is unstable and breaks down at a constant rate

nucleus

center of the atom

chemical bond

a bond between atoms of a compound; examples are covalent and ionic bonds

isotope

atom of an element that has a number of neutrons different from that of other atoms of the same element

ion

a charged atom

Vanderwaals forces

a slight attraction that develops between the oppositely charged regions of nearby molecules; allows geckos to climb walls

symbol

abbreviation of an element

covalent bond

bond in which electrons are shared between atoms

element

substance consisting entirely of one type of atom; these are found on the periodic table

proton

a positively-charged particle of an atom

compound

substance formed by chemical combination of 2 or more elements in definite proportions

molecule

smallest part of most compounds; a groups of atoms held together by covalent bonds

electron

negatively charged particle of an atom

ionic bond

bond formed when one or more electrons are transferred from one atom to another

neutron

the neutral particle of an atom

electrons

The chemical properties of an element are determined by the number of __ in the atom

atomic mass

The 3 of hydrogen-3 represents the element's ______

2 and 8

the first energy level holds ___ electrons; the second energy level holds ___ electrons

nitrogen, carbon, hydrogen, oxygen, phosphorus, sulfur

the 6 most common elements of living things!

2

number of electrons shared in a single covalent bond

4

number of electrons shared in a double covalent bond

6

number of electrons shared in a triple covalent bond

51

the number of protons in an atom of antimony (Sb); use the periodic table

51

the number of electrons in an atom of antimony (Sb)

71 (122-51)

the number of neutrons in an atom of antimony (Sb)

51

the atomic number of an atom of antimony (Sb)

122

the atomic mass of an atom of antimony (Sb)

electron

What subatomic particle of an atom determines the chemical properties of an element?

one atom of calcium, two atoms of oxygen, and two atoms of hydrogen

Name the elements present and the number of atoms of each in the formula: Ca(OH)2

positive

the charge of an atom that has lost an electron

negative

the charge of an atom that has gained an electron

12.5 grams (it went through 3 half-lives)

You have 100 g of carbon-14 (half-life is 5,780 years). How much is left at the end of 17,190 years?

NaCl

the chemical formula for table salt (sodium chloride)

O

the symbol for the element oxygen

all have 6

number of protons in carbon-12, carbon-13, and carbon-14

all have 6

number of electrons in carbon-12, carbon-13, and carbon-14

carbon-12 has 6, carbon-13 has 7, and carbon-14 has 8

number of neutrons in carbon-12, carbon-13, and carbon-14

all have 6

atomic number for carbon-12, carbon-13,and carbon-14

carbon-12 is 12; carbon-13 is 13; carbon-14 is 14

atomic mass for carbon-12, carbon-13, and carbon-14

H2O

chemical formula for water

H

symbol for hydrogen