1576153
| Questão | Responda |
| What is the Collision Theory | For a chemical reaction to happen, the atoms of the reactants have to collide with enough energy. |
| What factors speed up or affect a reaction? | - Temperature - Concentration - Surface Area - Catalyst |
| What does Temperature do to a reaction? | Higher temperature speeds up a reaction. Particles move faster because there is more kinetic energy. which leads to more frequent collisions and harder ones |
| What does Concentration do to a reaction? | A higher concentration means a faster reaction because more particles are likely to collide. |
| How does the Surface Area affect a reaction? | The larger the surface area the faster the reaction. More surface to collide with. |
| How does a Catalyst affect a reaction? | Doesn't get used up. Speeds up rate of reaction. Catalyst lowers the activation energy. |
| Why is the start of a reaction always the fastest? | Because there are more particles so they will collide often as they get used up they slow down. |
| What is Activation Energy? | The minimum amount of energy needed for the particles to react. |
| What does the rate of reaction depend on? | - Frequency of collisions between particles. - Energy with which particles collide. |
| What is Gas Pressure? | Every time gas particles hit the side of the container or each other. |
| What is the mass number? | The biggest number |
| What is the atomic/proton number? | Smaller number |
| How do you calculate the percentage by mass? | 1) Work out the RMM 2) Work out percentage. |
| How do you workout percentage yield? | Yield (what we made) ----------------------------------- x 100 The amount we should have made |
| What is atom economy? | The percentage of the reactant atoms that are converted into the desired product. |
| Atom Economy | RMM of desired product -------------------------------------- x100 RMM of all products or reactants |
| What are diamond and graphite both made out of? | CARBON |
| What is an Endothermic process | Bond Breaking |
| What is an exothermic process | Bond making |
| What happens in an Exothermic reaction? | They release energy and get hot |
| What happens in an Endothermic reaction? | They absorb energy and get cold |
| What happens if a reaction is Exothermic? | More energy released than needed. |
| What happens in an Endothermic reaction? | More energy is needed than released |
| What are the advantages of the Batch process? | - Cheap - Makes a fixed amount -Can be stored until needed |
| What are the disadvantages of the Batch Process? | - Inefficent - Expensive labour costs. |
| What are the advantages of continuous processing? | - Automated (24hrs) - Computer Controlled - Purer - Less energy needed |
| What are the disadvantages of the continuous process? | - Expensive equipment - Large amounts |
| Why are medicines so expensive? | - takes 10 years to develop and test a drug. - Long-term trials on humans are needed - Raw materials are often rare and costly. - Many raw materials are found in plants and are hard to extract. - Research needs to be independently verified |
| What is chromatography used for? | To test the purity of a compound by comparing the speed of movement against a known pure sample. Pure compounds have definite melting and boiling points. |
| What are allotropes? | An element in the same state but different structures. |
| Properties of diamond? | 1) Rigid 3D structure 2) No delocalised electrons ( does not conduct electricity) 3) high melting/ boiling point because of strong covalent bonds. |
| Properties of Graphite? | 1) 2D layered structure. 2) One delocalised electron (conducts electricity) 3) high melting/boiling points |
| Why do graphite layers slide over each other, while dimond is hard in every direction? | Bonded to 3 atom covalent bonds where as diamond is bonded to 4. |
| What are nanotubes? | Can be used in Catalyst systems. Atoms of the catalyst can be attached to the large surface area on the nanotubes. |
| How are chemicals extracted from plants? | Crushing, Boiling, dissolving and Chromatography. |
Quer criar seus próprios Flashcards gratuitos com GoConqr? Saiba mais.