chemical reactions Flashcards
what is corrosion?
corrosion is the gradual destruction of materials by chemical reactions with gases in the environment
what is galvanised iron?
galvanised iron is where you coat iron/stainless steel with paint or plastic to prevent rusting
what is combustion?
a chemical process in which a substance reacts rapidly with oxygen and gives off heat
cellular respiration equation
glucose + oxygen -> carbon dioxide + water
exothermic
releases heat, causing the temperature of the immediate surroundings to rise
endothermic
absorbs heat and cools the surroundings
what is matter?
matter is any substance that had mass and takes up space
what is matter made of?
atoms
left side of an equations
reactants
right side of an equations
products
What is the Law of Conservation of Mass?
The atoms of the starting materials (reactants) are rearranged in a chemical reaction to form new, different substances (products).
All of the original atoms are still present.
How is mass conserved?
More than one atom/molecule of each reactant/product can be involved in a reaction.
Why balance chemical equations?
We write balanced chemical equations to show that mass is conserved.
What are decomposition reactions?
In decomposition reactions one single compound breaks down into two or more simpler chemicals.
combustion reactions fall into the pattern….
fuel + O2 → CO2 + H2O
What are fuels?
Fuels are substances that release a lot of Energy (Heat) when combusted
Combustion of Hydrocarbons equation
Hydrocarbon + oxygen → carbon dioxide + water + energy
general equation for incomplete combustion is:
hydrocarbon + oxygen → carbon monoxide + carbon + water
Incomplete combustion occurs when…
the supply of air or oxygen is poor. Water is still produced, but carbon monoxide and carbon are produced instead of carbon dioxide.
How are respiration and combustion similar?
Respiration and combustion are superficially similar - the reactants and products are the same, and both are exothermic.
is respiration or combustion faster?
COMBUSTIONNNN!!!!
Why is energy released or absorbed?
Energy is stored in the chemical bonds of the reactants and products - chemical potential energy.
how are materials produced using chemistry?
Many substances and materials are made using a series of chemical reactions
