MYTUTOR SUBJECT ANSWERS

331 views

How do I balance symbol equations?

The most important thing to remember about chemistry equations, whether these are word or symbol equations, is that you must always have the same amount of each species (element or molecule) on both sides of the reaction arrow.
If you have 2 molecules of oxygen on the left hand side of the arrow you must also have 2 molecules of oxygen on the right hand side of the arrow.
Be careful not to get confused if elements appear as part of different combinations on either side of the arrow, for example if you have oxygen as a molecule in your reactants but as part of a hydroxide group in your products. You simply need to balance the total number of oxygen, no matter what form it appears in.

If we look at the symbol equation for the neutralisation of sulfuric acid:
H2SO4 + NaOH ---> Na2SO4 + H20 (remembering that the numbers should be subscript)

​There are currently 3 atoms of hydrogen on the left hand side of the arrow, and only 2 on the right hand side of the arrow. We can see that all the hydrogen in the hydroxide group of the sodium hydroxide has become part of the water molecule.
Therefore we need to balance the equation by multiplying the amount of reactants and products until there are the same number of hydrogen atoms on both sides of the equation.
We can do this by multiplying the amount of sodium hydroxide by 2, and the amount of water by 2 to give us:

​H2SO4 + 2NaOH ---> Na2SO4 + 2H2O

​There are now 4 atoms of hydrogen on both sides of the equation, and so it is completely balanced.

Kiani J. GCSE Biology tutor, A Level Biology tutor, GCSE Chemistry tu...

7 months ago

Answered by Kiani, who has applied to tutor GCSE Chemistry with MyTutor


Still stuck? Get one-to-one help from a personally interviewed subject specialist

218 SUBJECT SPECIALISTS

£20 /hr

Laura L.

Degree: Chemistry (MCHEM) (Masters) - Warwick University

Subjects offered:Chemistry, Maths+ 1 more

Chemistry
Maths
Biology

“Hi there! I'm a third-year Chemistry student, I tutor maths from 11+ to A level as well as GCSE Science, A level Biology, and Chemistry”

£22 /hr

Pooja D.

Degree: Medicine (Bachelors) - Birmingham University

Subjects offered:Chemistry, Science+ 6 more

Chemistry
Science
Physics
Maths
Biology
.UKCAT.
-Personal Statements-
-Medical School Preparation-

“I have tutored for the past 4 years and have gathered many ways of teaching concepts to students in a way that is easily-digestible and understandable. ”

Sahil M. A Level Biology tutor, GCSE Biology tutor, A Level Chemistry...
£20 /hr

Sahil M.

Degree: Medicine (Bachelors) - Manchester University

Subjects offered:Chemistry, Spanish+ 3 more

Chemistry
Spanish
Maths
Biology
-Medical School Preparation-

“Hello! My name is Sahil and I am currently a medical student at the University of Manchester. I am really looking forward to tutoring you in Spanish, Chemistry, Biology or Maths as well as trying to help you during the difficult proce...”

About the author

£18 /hr

Kiani J.

Degree: Biochemistry (Bachelors) - Liverpool University

Subjects offered:Chemistry, Physics+ 1 more

Chemistry
Physics
Biology

“Top tutor from the renowned Russell university group, ready to help you improve your grades.”

MyTutor guarantee

You may also like...

Other GCSE Chemistry questions

Name a test for a C=C double bond

Explain four ways of increasing the rate of a reaction

How can Diamond and Graphite both be made of carbon but be so different?

Why can ammonium sulfate be described as a salt?

View GCSE Chemistry tutors

We use cookies to improve your site experience. By continuing to use this website, we'll assume that you're OK with this. Dismiss

mtw:mercury1:status:ok