Answer:
Hands-free eyewash stations, sand bucket, fire blankets, fire extinguishers, fire alarm system and first aid kit.
Explanation:
Working in laboratories has many risks, therefore, preventive measures that should be incorporated to avoid the occurrence of any laboratory accidents.
Some of the important emergency equipment that should be available in laboratories are: hands-free eyewash stations, sand bucket, fire blankets, fire extinguishers, fire alarm system, chemical storage cabinet, first aid kits and fume hood.
Some of the personal protective equipment include lab coats, goggles, safety gloves and face shield.
When calcium carbonate is heated, it breaks down to form calcium oxide and carbon dioxide.
Thermal decomposition is the process in which heat is required.
It is also known as thermolysis.
It is processed in which a compound breaks into two or more products when the heat is supplied.
This reaction is used for the production of oxygen.
This reaction is also used for production of acidic as well as basic oxides.
CaCO3 on thermal decomposition gives:
CaCO3→CaO+CO2
CaO→ Basic oxide.
CO2→ Acidic oxide.
Answer:
A) Melting
Explanation:
The three changes of phase described in this problem are:
- Melting: melting occurs when a substance in solid state turns into liquid state. Since molecules in liquid state have more energy than molecules in solid state (because in liquids, molecules can slide past each other, while in solids they can't move, but only vibrate), thermal energy must be added in order to melt a substance
- Freezing: freezing occurs when a liquid substance turns into solid state (the opposite of melting). Since molecules in liquid state have more energy than molecules in solid state, thermal energy must be removed from the substance in order to cause freezing
- Condensation: condensation occurs when a gaseous substance turns into liquid state. Since molecules in gaseous state have more energy than molecules in liquid state, thermal energy must be removed from the substance in order to cause condensation
So the correct option is
A) melting
