,metals

Recall Questions and Answers

• Key Stage 2 Questions

  1. What is the variable that you measure during an experiment?

  • Answer: Dependent variable

  1. Which piece of equipment do we use to measure time?

  • Answer: A stopwatch or timer

• Key Stage 3 Questions

  3. Name one way we can prevent corrosion.

  • Answer: Paint the metal, apply oil, powder, or plastic, or use a layer of metal oxide.

  3. What gases produce acid rain?

  • Answer: Sulphur dioxide and nitrogen oxides.

  3. Name one way to reduce plastic waste.

  • Answer: Reuse, reduce, recycle, or repair your item.

Reactivity

• Definition of Reactivity:

  • Reactivity is the measure of how quickly an element can form a product during a reaction.

  • The reactivity series is a list of metals ordered by their reactivity, with the most reactive at the top and the least reactive at the bottom.

Chemical Reaction Indicators

• Signs that a chemical reaction is occurring include:

  • Fizzing

  • Gas released

  • Change in color

  • Light released

  • Bubbling

  • Change in temperature

Reactions with Oxygen and Water

• Metals can react with:

  • Oxygen:

  • Metal + Oxygen → Metal Oxide

  • Water:

  • Metal + Water → Metal Hydroxide + Hydrogen

• The vigor of the reaction indicates the metal's reactivity.

Group 1: Alkali Metals

• Properties:

  • 1 electron in the outer shell.

  • Soft metals, easily cut with a knife.

  • Loses 1 electron to form a +1 ion.

  • Low densities and low melting points.

  • Highly reactive metals.

  • Stored under oil to prevent reactions with oxygen or water.

• Reactivity Trends:

  • Reactivity increases down the group because:

  1. Atoms become larger.

  2. Outer electron is further away from nucleus.

  3. Outer electron experiences less attraction to the nucleus.

  4. Outer electron is more easily lost.

Reactions of Group 1 Metals

• Reaction equations:

  • Reaction with Oxygen:

  • Example: Lithium + Oxygen → Lithium Oxide

    • Equation: $4Li + O<em>2 → 2Li</em>2O$

  • Reaction with Water:

  • Example: Lithium + Water → Lithium Hydroxide + Hydrogen

    • Equation: $2Li + 2H<em>2O → 2LiOH + H</em>2$

  • Reaction with Chlorine:

  • Example: Lithium + Chlorine → Lithium Chloride

    • Equation: $2Li + Cl_2 → 2LiCl$

• Vigorousness of Reaction:

  • Lithium: doesn’t melt, slower, produces hydrogen gas, fizzes.

  • Sodium: bubbles of H2 gas, melts, reacts quicker.

  • Potassium: Vigorous reaction, produces lilac flame.

Safety Precautions

• Always wear safety goggles during metal reactions and maintain a safe distance.

Self Assessment & Revision Tasks

• Use your textbook or notes to help complete exercise sheets.

• Reflect on lesson and note keywords and their definitions.

• RAG your knowledge of lesson topics to identify areas for improvement.

True or False Questions

• 1. Metals are found on the right-hand side of the periodic table. FALSE

• 2. Metals react with oxygen to form metal hydroxides. FALSE

• 3. Potassium lithium is the least reactive group 1 metal. FALSE

• 4. A property of group 1 metals is that they have a low density. TRUE

• 5. Group 1 metals react with water to release carbon dioxide gas. FALSE