Periodic table

• What is the reaction of lithium with oxygen?

  Lithium burns with a strongly red-tinged flame and produces a white solid.
• What happens when lithium reacts with water?

  Lithium fizzes steadily and gradually disappears, producing a white powder that settles on the sides of the container.
• What is produced when sodium reacts with oxygen?

  Sodium burns with a bright yellow flame and produces a white solid.
• Describe the reaction of sodium with water.

  Sodium fizzes rapidly, melts into a ball, and disappears quickly, producing clouds of white powder that settle on the sides of the container.
• What is the flame color produced by potassium during a reaction with oxygen?

  Potassium produces a lilac flame.
• How does potassium react with oxygen compared to sodium?

  The reaction of potassium is even more vigorous than with sodium.
• What are the characteristics of Group 0 (Noble gases)?

  • 8 electrons in their outer shell (except helium, which has 2)
  • Full outer shells lead to unreactivity
  • Boiling points increase with increasing relative atomic mass down the group
• What are the properties of Group 7 (Halogens)?

  • Seven electrons in their outer shell
  • Non-metals existing as molecules made of pairs of atoms
  • React with metals to form ionic compounds with -1 charge halide ions
  • React with nonmetals to form covalent compounds with shared pairs of electrons
  • Relative molecular mass, melting point, and boiling point increase down the group
  • Reactivity decreases down the group due to increased electron shells
• How do halogens react with metals and nonmetals?

  Halogens react with metals to form ionic compounds and with nonmetals to form covalent compounds.
• Why does reactivity decrease down Group 7 (Halogens)?

  Reactivity decreases because the number of electron shells increases, reducing the attraction for electrons.
• What happens when a more reactive halogen displaces a less reactive one in a solution?

  A more reactive halogen can displace a less reactive one in an aqueous solution of its salt.
• What is the general arrangement of elements in the periodic table?

  Elements are arranged in order of atomic (proton) number and similar properties are grouped in columns.
• What do elements in the same periodic group have in common?

  Elements in the same group have the same number of electrons in their outer shell, leading to similar chemical properties.
• What were the contributions of John Newlands and Dmitri Mendeleev to the periodic table?

  John Newlands:

  • Ordered elements by atomic weight
  • Noticed similar properties every eighth element (law of octaves)

  
  

  Dmitri Mendeleev:

  • Ordered elements by atomic mass, with some adjustments
  • Left gaps for undiscovered elements
  • Established the periodic table based on regular intervals of similar properties
• How did the modern periodic table improve upon Mendeleev's table?

  The modern periodic table incorporates discoveries of isotopes and orders elements by atomic (proton) number.
• What defines metals and non-metals in the periodic table?

  Metals:

  • React to form positive ions
  • Majority of elements, found on the left and bottom of the periodic table

  
  

  Non-metals:

  • Do not form positive ions
  • Found on the right and top of the periodic table
• What are the characteristic properties of Group 1 (Alkali metals)?

  • Single electron in their outer shell
  • React vigorously with water to create alkaline solutions and hydrogen
  • React with oxygen to form oxides
  • React with chlorine to form white precipitates
  • Reactivity increases down the group