Let's React

• Structure of an atom

  nucleus made up of protons and neutrons; the electrons make up the surrounding area

  
• What is meant by a neutral atom?

  When Protons = Electrons
• Where the protons, neutrons, and electrons are in an atom?

  nucleus made up of protons and neutrons; the electrons make up the surrounding area
• Charges on protons, neutrons and electrons

  Proton = Positive

  Neutrons = Neutral

  Electrons = Negative
• How are electrons arranged in atoms?

  2,8,8,2
• How are ions formed?

  When atoms lose (Cation) or gain (Anion) electrons/when electrons are transferred between atoms.
• Why are outer shell/valence electrons are important?

  Where main properties come from, more stable
• difference between cations and anions

  cations = positive charge, anions = negative charge
• Why do metals form cations?

  metals lose electrons to form cations because they have relatively empty valence shells, so this is the easiest way for them to achieve the electron configuration of a noble gas.
• Why do non-metals form anions?

  Easier to gain a few outer electrons to achieve a full outer level than lose a lot
• How do bonds form between ions?

  the transfer of electrons, forms an ionic bond
• What is the Law of Conservation of mass in chemical reactions?

  during a chemical reaction, matter cannot be created or destroyed
• Describe how to do an experiment to show the law of conservation mass


  (Balloon experiment)
• How do you do calculations based on the Law of Conservation of mass?

  Reactants = Products
• What is the difference between physical and chemical change?

  Physical is easy to reverse e.g tearing paper, changing state.

  Chemical is when a new substance has been formed. COBALT
• List experimental observations that indicate a chemical change. (COBALT)

  Colour change

  Odour change

  Bubbles appearing

  Appearance or disappearance of a solid

  Light or sound produced

  Temperature change (qualitative - hot/warm/cold)
• Write formulas for ionic compounds

  -Positive ion first, then negative ion

  -Positive charge must balance negative charge

  -Paranthesis around polyatomic ions that appear more than once
• How to write word equations

  all the reactant on the left -> all the products on the right.
• How to balance a chemical equation

  1. make sure each individual compound makes sense (is neutral) 2. take inventory of the atoms for each side of the equation. 3. Add coefficients which should help to make the same number of atoms on each side of the equation. 4. Check the equation by taking another inventory on each side.

  
  

  Add the coefficients where it is needed to have both sides of the equation equal each other.

  
  

  In a balanced chemical equation, the numbers of atoms of each element and the total charge are the same on both sides of the equation.
• Explain the parts of a chemical equation

  The starting compound(s)—the reactants—on the left and the final compound(s)—the products—on the right, separated by an arrow.
• Define the term 'rate' when describing chemical reactions

  The speed of the reaction
• List the factors that affect the rate of reaction

  1. Increased temperature

  2. Increased concentration of dissolved reactants

  3. Increased surface area of solid reactants

  4. Use of catalyst
• Why does increased temperature increase the rate of reaction?

  At a higher temperature, particles have more energy. Meaning they move faster (more likely to collide with other particles. This then means that when they collide they do so with more enegry so the number of successful collisions increases.
• Why does increased concentration increase the rate of reaction?

  At a higher concentration, there are more particles in the same amount of space. Meaning the particles are more likely to collide and therefore more likely to react.
• Why does increased surface area increase the rate of reaction?

  If the solid is split into several pieces, the surface area increases. The smaller the pieces, the larger the surface area. This means more collisions and a greater chance of reaction.
• Why does the use of a catalyst increase rate of reaction?

  - a catalyst speeds up a chemical reaction

  - A catalyst provides a surface for the reaction to take place on and hence increases the frequency of collisions.

  - also provides a different pathway for the reaction with lower energy required.
• Why are catalysts so important for industry?

  - products can be made more quickly (saves time and money)

  - reduce the need for high temperatures (saves fuel and reducing pollution

  - catalysts are reusable (can be recovered chemically unchanged)

  - Biological catalysts are called enzymes.
• Chemical reaction


  Needs to occur more quickly
• Processes a chemist has to speed up a reaction

  • 5 ways
• Characteristics of collisions that lead to dates

  • Correct orientation to knock books out of hands
  • Enough energy to knock books out
• Harriet's story


  Parallels to chemical reaction rates
• 5 changes to schools to facilitate more book-dropping collisions

  1. Shrink hallway size

  2. Increase school population

  3. Reduce time between classes

  4. Students stop traveling in packs

  5. Hire a matchmaker
• Shrinking reaction vessel/mixture


  Increases collisions between particles
• Increasing temperature


  Increases particle velocity and energy of collisions
• Increasing surface area


  More particles available for collisions
• Catalyst


  Lowers activation energy by bringing particles together and orienting them correctly
• (A) Structure of an atom

  nucleus made up of protons and neutrons; the electrons make up the surrounding area

  
• (A) What is meant by a neutral atom?

  When Protons = Electrons
• (A) Where the protons, neutrons, and electrons are in an atom?

  nucleus made up of protons and neutrons; the electrons make up the surrounding area
• (A) Charges on protons, neutrons and electrons

  Proton = Positive

  Neutrons = Neutral

  Electrons = Negative