Lecture 1

Question 1

Atoms (protons)

Answer 1

mass = 1amu
positively charged

Question 2

Atoms (neutrons)

Answer 2

mass = 1 amu
neutral, no charge

Question 3

Atoms (electrons)

Answer 3

mass = less than 1 amu
negatively charged

Question 4

elements

Answer 4

pure substances, with atoms
same number of protons
chemical properties determined by number of protons and electrons

Question 5

atomic number

Answer 5

Z (number of protons)

Question 6

isotopes

Answer 6

atoms of an element with the same no. of protons but different number of neutrons
defines its chemical properties

Question 7

ions

Answer 7

electrons gained or loss, charged ions
positive = cations, anions = negative
H+ = protons

Question 8

compounds

Answer 8

elements going through chemical reactions
rearranged into compounds
more than one element
held together by chemical bonds
molecular and ionic compounds

Question 9

ionic compounds

Answer 9

non metal and metal reacting
electrostatic attraction between positive and negative ions
high melting point, conduct electricity in molten or liquid

Question 10

molecular compounds

Answer 10

covalent compounds
atoms share the electron
non metal
low melting and boiling pointnt

Question 11

interactions of covalent compounds

Answer 11

weak interactions between a molecule
strong interactions within a molecule