Science

• What does the modern periodic table show?

  Every known element
• Who designed the first periodic table?

  Mendeleev
• How did Mendeleev arrange the elements in his periodic table?

  In rows or columns in order of atomic weight
• Why did Mendeleev leave gaps in his periodic table?

  For elements that had not been discovered yet
• What is the main difference between Mendeleev's periodic table and the modern periodic table?

  The modern table arranges elements by atomic number instead of atomic weight
• How are elements arranged in the modern periodic table?

  According to their atomic number (the number of protons)
• What does it mean for elements to be grouped together in the periodic table?

  They have similar properties
• What are the key features of the periodic table?

  • Metals are on the left of the stepped line
  • Non-metals are on the right of the stepped line
  • Columns are called groups
  • Rows are called periods
  • Group 1: Alkali metals
  • Group 2: Alkali earth metals
  • Group 7: Halogens
  • Group 0: Noble gases
• What is a property in the context of substances?

  A property describes how a substance looks and how it reacts with other substances
• What is a chemical property?

  How the substance reacts with other substances
• What is a physical property?

  How the substance acts on its own
• What are the properties of metals?

  • Conductors of thermal energy and electricity
  • Ductile (can be stretched into a wire)
  • High density
  • Sonorous (makes a ringing sound)
  • Malleable (can be bent into a shape)
• What are the properties of non-metals?

  • Poor conductors of thermal energy and electricity
  • Brittle (can snap easily)
  • Low density
  • Not sonorous
• What happens when a metal reacts with water?

  It produces a metal hydroxide and hydrogen
• What is the general reaction equation for a metal reacting with water?

  metal + water → metal hydroxide + hydrogen
• Do non-metals react with water?

  No, they do not react with water
• What do non-metals react with to form non-metal oxides?

  Oxygen
• What is the general reaction equation for a non-metal reacting with oxygen?

  non-metal + oxygen → non-metal oxide
• What do non-metal oxides react with to form?

  Acidic solutions
• What are halogens known for?

  They are very reactive and hazardous elements
• What type of reactions can halogens participate in?

  Displacement reactions
• What is a displacement reaction?

  When a more reactive element displaces a less reactive element from its compound
• Give an example of a displacement reaction involving chlorine and potassium bromide.

  chlorine + potassium bromide → bromine + potassium chloride
• Why does chlorine displace bromine in the reaction with potassium bromide?

  Chlorine is more reactive than bromine
• How does the reactivity of Group 1 metals change down the group?

  The reactivity increases as you go down the group
• How does the reactivity of Group 7 elements change down the group?

  The reactivity decreases as you go down the group
• What is the reactivity of Group 0 elements?

  They are very unreactive (inert)
• What are the physical properties of Group 0 elements?

  They have low melting and boiling points, so are gases at room temperature