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Chemical Equations | Environmental Chemistry | Chemistry | FuseSchool

Chemical Equations | Environmental Chemistry | Chemistry | FuseSchool

chemical

equations

can sometimes look a bit daunting especially when there are lots of different compounds and state symbols involved but fear not to help in this lesson about

chemical

equations

quite simply a

chemical

equation shows the overall

chemical

change of reactants into products it's a bit like a detailed cooking recipe but where all the ingredients and all the products are written down even the ones you can't necessarily see the reactants are what you start with and the
chemical equations environmental chemistry chemistry fuseschool
products are what are formed there are two ways of writing

chemical

equations

word

equations

and symbol

equations

when they're written both types show the reactants on the left of an arrow and the products on the right the arrow is there to show that the reaction is irreversible if you like it shows the direction of the reaction and that it is one way a bit like a one-way street you can't reverse along a one-way street and you can't reverse an irreversible reaction let's look at
a word equation this is a way of summarizing a

chemical

reaction for example the neutralization of hydrochloric acid with sodium hydroxide we would write sodium hydroxide plus hydrochloric acid then the arrow sodium chloride plus water the plus sign indicates that there is more than one reactant or product on each side of the equation and you'll note that the reactants are on the left and the products are on the right we've also written this all on a single line it makes it a lot easier
chemical equations environmental chemistry chemistry fuseschool
to read this way so when you write your

equations

try to keep all of the information on a single line if you can't then the arrow becomes an important separator the rule of reactants on the left and products on the right still applies because if not the equation can become a jumbled mess a clearly written equation is always easier to understand a word equation provides a good summary but a symbol equation provides more information it shows more detail and allows us to see how many atoms and
molecules are involved in each reaction so if we look at the neutralization equation again the symbol equation is written naoh plus hcl as the reactants then an arrow to indicate the irreversible reaction which gives nacl plus h2o as the products the little letters in brackets are state symbols they show the state of matter of each product and reactant and this is covered in more detail in our lesson state symbols in

chemical

equations

there are occasions where a reaction is reversible due to
chemical equations environmental chemistry chemistry fuseschool
the changes in the surroundings for example pressure concentration ph and temperature and where this is the case we draw a double arrow made of two half arrows pointing in opposite directions and this indicates that the reaction can go either way the formation of ammonia from nitrogen and hydrogen is an example of a reversible reaction and the key thing here is that you recognize the reversible reaction by the double arrows and you'll note some numbers in front of the hydrogen and ammonia
formulae and these are there to make the equation balance you can find out more about this in our balancing

equations

lesson and so to summarize a

chemical

equation shows the overall

chemical

change of reactants into products we usually write reactants on the left of the arrow and products on the right a single arrow means that the reaction is irreversible and two oppositely pointing half arrows means the reaction is reversible and that completes our overview of

chemical

equations

you