Period 3 Elements Flashcards
How does sodium react with water?
-Reacts vigorously with cold water
-Forms a molten ball on surface
-Fizzes
-Produces H2 gas
What is the equation for sodium reacting with water?
2Na(s)+2H2O(l)–>2NaOH(aq)+H2(g)
How does magnesium react with water?
-Reacts very slowly with cold water
-Forms a weak alkaline solution
What is the equation for magnesium reacting with water?
Mg(s)+2H2O(l)–>Mg(OH)2(aq)+H2(g)
How does magnesium react with steam?
-Reacts much faster than with cold water
What is the equation for when magnesium reacts with steam?
Mg(s)+H2O(g)–>MgO(s)+H2(g)
What is the general equation for a period 3 element reacting with oxygen?
Element+Oxygen–>Oxide
What colour flame does sodium produce?
-Yellow
What colour flame does magnesium produce?
-Bright white
What colour flame does aluminium produce?
-N/A
What colour flame does silicon produce?
-N/A
What colour flame does phosphorus produce?
-Bright white
What colour flame does sulfur produce?
-Blue
How do Na and Mg react with air?
-Vigorously
How do Al and Si react with air?
-Slowly
How does P react with air?
-Spontaneously combusts
How does S react with air?
-Burns steadily
Why do Na2O, MgO and Al2O3 have high melting points?
-Giant ionic lattices
-Strong forces of attraction between each ion
Why does MgO have a higher melting point than Al2O3?
-Al2O3 is slightly covalent
-Electronegativity between Al and O isn’t as large as between Mg and O
Why does SiO2 have a higher melting point than other non-metal oxides?
-It has a macromolecular structure
Explain why SiO3 and P4O10 have low melting points?
-Simple covalent molecules
-Dipole-dipole and van der waals forces which are weak
Why does sodium oxide make a more alkaline solution than magnesium oxide when reacting with water?
-NaOH is more soluble in water
-More hydroxide ions form
What is the equation for sodium oxide reacting with water?
Na2O(s)+H2O(l)–> 2NaOH(aq)
What is the equation for magnesium oxide reacting with water?
MgO(s)+H2O(l)–>Mg(OH)2(aq)
What is the equation for phosphorus oxide reacting with water? What acid is formed?
P4O10(s)+6H2O(l)–>4H3PO4(aq)
-Acid=phosphoric(V) acid
What is the equation for sulfur dioxide reacting with water? What acid is produced?
SO2(g)+H2O(l)–>H2SO3(aq)
-Acid=sulfurous acid/sulfuric(IV) acid
