metals and non metals Flashcards
properties of metals
have 1-3 electrons in the outer shell of each metal atom strong Malleable can be polished high melting and boiling point solid at room temp ( mercury ) good conductors heat good conductors of electricity react with Oxygen to form basic Oxides when they form Ions they are positive high density dissolve in mineral acids normally releasing hydrogen
properties of non metals
usually have 4-8 electrons in their outer shell Brittle poor conductors of electricity poor conductors of heat low melting and boiling temp react with Oxygen to form acidic oxides when they form Ions they are negative ( except Hydrogen ) low density dull
list 5 common metals
Sodium Magnesium copper Aluminium lithium zinc
they generally end in ium or um
list 5 non metals
hydrogen nitrogen helium Oxygen Chlorine
the majority of the chemical elements in pure form are classified as metals, how can they be divided
by chemical and physical properties
periodic table can be divided into 3 metal groups
metals
non metals
metaloids
Metals that react with OXYGEN produce oxides as their products.
give 3 examples
Sodium burns quickly with a bright yellow flame. Na2O, sodium peroxide - a yellow powder.
Magnesium Burns with a brilliant white flame. MgO, magnesium oxide - a white ash.
Copper Does not burn. Metal eventually coats with a black layer. CuO, copper oxide - a black powder.
Magnesium and Sodium;
Toxic white fumes
freshly cut it dulls by oxide layer from oxygen in air
form peroxides - higher oxides that are vigorous oxidising agents
Some metals also react with WATER, but like their reaction with oxygen, they react in different ways
give 3 examples
Most metals react with water to
metal oxide or hydroxide
the most reactive liberate hydrogen …in large quantities explosive
Sodium Very vigorous reaction with cold water. Floats. Can be lit with a lighted splint. 2nd. Sodium hydroxide, NaOH and hydrogen gas.
Magnesium Very slow with cold water, but vigorous with steam. 4th. Magnesium oxide, MgO and hydrogen gas.
Copper No reaction with steam.
Let’s now look at the reaction between metals and acids to see if they can also help distinguish difference in reactivity
3 examples
Magnesium Vigorously reacts with a stream of gas evolving. 1st - most reactive. Magnesium chloride, MgCl2 and hydrogen gas.
Iron Slow reaction with a gentle stream of gas evolving. 3rd. Iron chloride, FeCl2 and hydrogen gas.
Copper No reaction. 5th - least reactive
Define metaloids
A metalloid is a chemical element that has properties that are in between or a mixture of those of metals and nonmetals and is consequently difficult to classify unambiguously as either a metal or a nonmetal
List 3 Metaloids
Boron B
Silicone Si
Arsenic A
from a firefighting point why not use water on large quantities of reactive metals
how should one extinguish
poss formation of hydrogen which in large quatitie swill be explosive
high pressure jets will disperse powdered or molten metal spreading the fire and increasing intensity
small quantities dry powder or sand
list the activity series of metals and reaction to cold water
Potassium react to give flammable Hydrogen
Sodium leaves metal hydroxide a corrosive
Barium Alkali
Strontium Small piece of sodium moves rapidly
Calcium across surface
Magnesium react little with water Aluminium hot metals decompose water Chromium steam produces hydrogen Manganese Zinc Cadmium Iron
Cobolt little reaction unless white hot and steam
Nickel
Tin
Lead
Bismuth inactive to water or steam
Copper
Mercury
Silver
Platinum
Gold
Reaction of metals in activity series to Oxygen
P react readily in air ( contains O ) S Pottasium and Sodium r contained in Parraffin B S C
M A C M Z C
C
N
T will still burn at very high temps
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