Simple reactions ( MEMORISE ) Flashcards
General (19 cards)
What is the appearance of carbon at room temperature?
Carbon is a black solid.
What is the appearance of oxygen at room temperature?
Oxygen is a colourless, odorless gas.
What type of reaction occurs between carbon and oxygen?
A combustion reaction (exothermic).
Define a combustion reaction.
A chemical reaction in which a substance reacts with oxygen, releasing heat and light.
What is a redox reaction?
A reaction where oxidation and reduction happen at the same time.
What happens when carbon burns in oxygen?
It glows red or orange. Carbon is oxidised and oxygen is reduced.
What is the word and symbol equation for carbon reacting with oxygen?
Carbon + Oxygen → Carbon dioxide
C(s) + O₂(g) → CO₂(g)
What is the appearance of hydrogen at room temperature?
Hydrogen is a colourless, odorless gas.
What happens when hydrogen reacts with oxygen?
A highly exothermic combustion reaction that may be explosive.
What are the signs of hydrogen reacting with oxygen?
A squeaky pop, bright flame, and the release of heat, light, and sound.
What is activation energy?
The minimum energy required for a chemical reaction to occur.
Why is activation energy needed for hydrogen and oxygen to react?
Because they are stable at room temperature, so energy is needed to break the bonds.
What is the word and symbol equation for hydrogen reacting with oxygen?
Hydrogen + Oxygen → Water
2H₂(g) + O₂(g) → 2H₂O(l)
What does sodium look like?
A shiny, soft, silver metal.
What does chlorine look like?
A pale green-yellow gas.
What type of reaction is sodium + chlorine?
Synthesis/combination and redox reaction (exothermic).
What happens when sodium reacts with chlorine?
Sodium fizzes, heats up, a bright yellow-orange flame appears, white smoke forms, and a white solid (NaCl) is produced.
Why is a drop of water needed to start the reaction between sodium and chlorine?
It removes the sodium oxide layer, allowing the sodium to lose electrons and react with chlorine.
What is the word and symbol equation for sodium reacting with chlorine?
Sodium + Chlorine → Sodium chloride
2Na(s) + Cl₂(g) → 2NaCl(s)
