chap 2 the chem of life

Question 1

building from scratch: atoms and elements

atom

Answer 1

smallst unit of matter capable of retaining the identity of an element during a chemical reaction

Question 2

building from scratch: atoms and elements

element

Answer 2

a substance that cannot be broken down into simpler substances by normal chemical reactions

on the periodic table

Question 3

building from scratch: atoms and elements

there are ________ naturally occuring elements and ________ artifically made

Answer 3

98
20

Question 4

building from scratch: atoms and elements

the 6 elements that make up 95% of all living material

CHNOPS

Answer 4

C: carbon
H: hydrogen
N: nitrogen
O: oxygen
P: phosphorus
S: sulfur

Question 5

building from scratch: atoms and elements

atoms are made up of the subatomic particles

Answer 5

protons
neutrons
electrons

Question 6

building from scratch: atoms and elements

protons
neutrons are in the

Answer 6

atom’s nucleus

Question 7

building from scratch: atoms and elements

clouds of electrons are

Answer 7

orbitting the nucleas

Question 8

building from scratch: atoms and elements

the atomic weight or mass of an atom is the

Answer 8

total number of protons and neutrons in its nucleus

Question 9

building from scratch: atoms and elements

atomic number of an atom is its number of

Answer 9

protons

conveniently atoms that are electrically neutral have the same number of positive charges as negative charges

Question 10

building from scratch: atoms and elements

opposite charges attract so negatvely charged electrons are attracted to

Answer 10

positively charged protons

the attraction holds electronsin orbits