Unit 2 Flashcards
Periodic Table
What does the property of an element depend on?
Atomic number (protons)
How is the periodic table arranged?
In atomic numbers
How many electrons does each orbital hold?
S P D F
2
6
10
14
What does a period tell you?
Energy level. (number of shells)
What does group tell you?
Number of valence electrons
Trends in atomic radius
↓← Decrease across a period is due to more protons meaning more attraction
Increase down a group is due to shielding
What is ionisation energy?
Amount of energy needed to remove an electron from an atom in gas phase
Trend in ionisation energy?
↑→ increases across a period as more protons and no increased shielding.
Decreases down a group as shielding increases
What is metallic character?
How readily an atom can lose an electron. So highly electronegative elements (eg) fluorine have very little metallic character
Trend in metallic character?
↓← (opposite of ionisation) more shielding less attraction to the nucleus
Properties of metals?
Good electric and heat conductors. Malleable Solid at room temp Lose valence shells easily Reducing agent
Non metal properties
Poor electric and heat conductors brittle many forms at room temp Gain valence shells Oxidizing agent
what is a hydride?
Compound formed by hydrogen and another element only
What are covalent hydrides?
H+ Non- metal
What are ionic hydrides?
H+ metal