periodic properties of elements (7.6-7.8)

Question 1

What happens if an electron has low ionization energy?

Answer 1

It is highly reactive

Question 2

How are metals different than nonmetals?

Answer 2

• metals tend to form cations ( hydrogen has a special property)
• nonmetals tend to form anions (alkali metals 1+, alkali earth metals 2+, transition 3+)

Question 3

What is a metal?

Answer 3

• most metal oxides are ionic solids that are basic
• shiny, conduct heat/electricity, solid at room temp (except mercury) low ionization energies, lose electrons to form cations

Question 4

What is Metal Chemistry?

Answer 4

• compounds formed between metal and nonmetal tend to be ionic
  NaCL
  Na= metal -1
  Cl= nonmetal +1
• metal oxides tend to be basic and react with acids (NiO)
  Ni= metal, 2+
  O= 2-

Question 5

What are nonmetals?

Answer 5

• most nonmetal oxides are molecular substances that form acidic solutions
• are found on the right hand side of periodic table, form molecular compounds, solid/liquid/gas (depends on element), dull, poor conductors, brittle, exist as anions or oxyanions in ionic compounds with metals negative/positive oxidation states in compounds with nonmetals

CO2(g)+H2O(l)-> H2CO3 (aq) carbonic acid/ carbonated water

Question 6

Are metal oxides basic or acidic?

Answer 6

basic

Question 7

What are metal oxides?

Answer 7

• most metal oxides are ionic solids that are basic
• alkali metal oxides dissolve in water to form the metal hydroxide
  Na2O(s)+ H2O(l)-> H2CO3 (aq)
• many other wise insoluble metal oxides will dissolve in an acid

Question 8

What are allotropes?

Answer 8

different molecular forms of one element (different forms of the same elements)
- oxygen (O2) Dioxygen gas, (O3) ozone gas
MOST STABLE FORM IS STANDARD STATE FOR ENTHALPIES OF FORMATION

Question 9

Group Reactivity & Property Trends
(group 1) alkali metals

Answer 9

• soft, metallic, soft, found only in compounds in nature, not in their elemental form, typically metallic properties (luster conductivity)

Properties: low density, low melting point, low ionization energies, form+1, losing valence S electron, highly reactive in water

Na(s)+ H2O (l) -> NaOH+ 1/2H2(g)

Question 10

Group Reactivity & Properties (group 2) alkali earth metals

Answer 10

• reactivity tends to increase as you go down the group
• beryllium doesn’t react to water, magnesium reacts with only steam but the other alkaline earth metals react readily with water
  Ca(s)+2H2O(l) -> Ca(OH)2+ H2 (g)

Question 11

Group Reactivity & Properties (group 6A) chalcogens

Answer 11

• increasing in metallic character down the group
• oxygen, sulfur, and selenium are NONMETALS
• O2 is a gaseous element, S8 is a solid element (at the ambient condition), tellurium is a metalloid

Trends: Oxygen is more likely to form a -2 anion; polonium is most likely to have a positive charge

Question 12

Group Reactivity & Properties (group 7A) halogens

Answer 12

• nonmetals, form diatomic molecules. gain one electron to form anions with noble gas configuration (closed shell). react directly with metals to form metal halides. react with hydrogen to form hydrogen halides.

Question 13

Group Reactivity & Properties (8A) noble gas

Answer 13

• very large ionization energies. their electron affinities are positive (they can’t form stable anions). they are mostly unreactive, they are found as monatomic gases.

Question 14

What is hydrogen?

Answer 14

• elemental H2 gas, like halogens
• unique: forms both H- and H+ in compounds and acts as a metal or nonmetal
• hydrogen halides like HCL are gaseous neutral molecules, acidic in solution forming H+
• when reacting with metals, forms hydride anions (H-)
  MgH2
• compounds with carbon-basis for organic chemistry
  CH4