Reactions Flashcards
How do you tell if something is a chemical reaction?
Bubbles, rusting, colour change, baking and burning are types of chemical change. Chemical changes make new substances whereas physical changes usually involve a change of state.
How do you tell if something is a physical change?
Dissolving, freezing, cutting, melting and boiling are physical changes.
What happens to the particles in a chemical reaction?
The particles are rearranged to produce a new substance.
What are catalysts?
They help speed up the rate of a reaction.
What are the reactants and products in the equation:
Magnesium + Oxygen —> Magnesium Oxide
Magnesium and oxygen are the reactants. Magnesium oxide is the product.
What is a fuel?
A material that releases energy in the form of heat such as coal, oil and gas.
What is combustion?
Combustion is another word for burning.
What is the equation for burning?
Fuel + Oxygen —> Carbon Dioxide + Water
What is thermal decomposition?
When a chemical substance breaks down (decomposes) due to heat into at least 2 chemical substances.
What are the products of the decomposition of calcium carbonate?
Calcium oxide and carbon dioxide.
What is the law for the conservation of mass?
Mass of Reactants = Mass of Products
What do exothermic reactions show?
An increase in temperature, for example burning fuels. It makes the surroundings warmer by taking heat from the object and transferring it to the surroundings.
What do endothermic reactions show?
A decrease in temperature for example sports ice packs. They make the surrounding colder by taking heat from the surroundings and transferring it to the object.
What is the law of conservation of mass?
- Mass is never gained or lost in a chemical reaction.
- When a reaction happens, the atoms in the chemicals are rearranged into different compounds. No new atoms are created and no atoms can disappear.
What are the 3 things in the fire triangle?
Oxygen, fuel, heat (ignition).
What do fuels react with to produce energy in an exothermic reaction?
Oxygen.
What is reduction?
When oxygen is removed from a chemical in a reaction.
What is oxidation?
When oxygen is added to a chemical in a reaction.
Which 3 metals do not react with oxygen and why?
Silver, gold and platinum because they are lower down in the reactivity series.
What is the word equation for the combustion of methane?
Methane + Oxygen –> Water + Carbon Dioxide
What is metal carbonate?
A compound which contains metal (Ca, Cu, Mg), carbon and oxygen. Eg: CuCO3, CaCO3.
What is a foam extinguisher used for?
It is to be used on class A and class b fires and it removes the parts heat and oxygen from the fire triangle.
What is a water extinguisher used for?
It is to be used on class A fires and it removes the part heat from the fire triangle.
What is a CO2 extinguisher used for?
It is to be used on class B fires and it removes the part oxygen from the fire triangle.
