An addition reaction is a reaction in which new atoms are added to the organic compound by converting carbon-carbon double covalent bonds to carbon-carbon single covalent bonds.
Month: January 2021
Differences between boiling and evaporation
| Boiling | Evaporation |
| Occurs at a fixed temperature | Occurs at any temperature below boiling point |
| Quick process | Slow process |
| Takes place throughout the liquid | Takes place at the surface of the liquid |
| Bubbles form | No bubbles |
| Temperature remains constant | Temperature may vary |
| Thermal energy supplied by energy source | Thermal energy supplied by surroundings |
What is a homologous series?
A homologous series is a family of organic compounds with:
– same functional group
– same general formula
– similar chemical properties
– gradual change in physical properties
Examples of homologous series:
– Alkanes
– Alkenes
– Alcohols
Advantages and Disadvantages of a Thermocouple Thermometer
| Advantages | Disadvantages |
| Can measure a wide range of temperature, from -100 deg C to 2500 deg C | Low sensitivity to small temperature changes |
| Can measure temperature at a point | Relatively low accuracy, degree of error is 1 deg C to 2 deg C |
| Rugged, not easily damaged | Prone to corrosion, due to two metals of different reactivity being in contact |
| Respond quickly to temperature changes | Low voltage output, which makes the output easily distorted by interference from nearby electronic devices. |
What is “inertia”?
Inertia refers to the reluctance of the object to change its state of rest or motion.
The bigger the mass of a body, the greater its inertia.
(ie, the bigger the mass, the more difficult it is to make a stationary object move, or to make a moving object change its speed or direction, due to its inertia)
State the Principle of the Conservation of Energy
The Principle of the Conservation of Energy states that energy cannot be destroyed or created.
It can only be converted from one form to another, or transferred from one body to another.
The total energy in the system remains constant.
Describe the structure of metals and metallic bonds.
The structure of metal consists of positive metal ions, arranged in a regular pattern, floating in a sea of delocalized electrons.
Metal atoms have the tendency to lose their valence electrons to form positive ions.
These valence electrons become delocalized and form a ‘sea of mobile electrons’ around the positive ions.
The strong electrostatic force of attraction between the positive metal ions and delocalized electrons form strong metallic bonds.
The layers of metal ions can slide over one another when sufficient force is applied.
