Skip to content
This repository was archived by the owner on Jan 5, 2024. It is now read-only.

Syntax

Jump to bottom
XiaoJSoft edited this page Dec 18, 2017 · 4 revisions

Syntax

Basic syntax

The BCE syntax is simple and just like the hand-writing style. For example:

>> Na2CO3+HCl=NaCl+H2O+CO2
Na2CO3+2HCl=2NaCl+H2O+CO2

Here are the basic rules:

  1. Use '=' to separate the reactants and the products.
  2. Use '+' to connect each substance.
  3. The syntax of the atom symbol is case-sensitive. The first letter of one atom symbol must be upper-case and others must be lower-case.

In one molecule, you can specify the charge by adding "<{n}e+>" or "<{n}e->" at the end. {n} is a variable and it can be ignored if {n} equals to 1. For example:

>> Cl2+<e->=Cl<e->
Cl2+2<e->=2Cl<e->
>> Cu+Fe<3e+>=Cu<2e+>+Fe<2e+>
Cu+2Fe<3e+>=Cu<2e+>+2Fe<2e+>

Equations with multi-solutions are also supported. For example:

>> C+O2=CO+CO2
{2*Xa+2*Xb}C+{Xa+2*Xb}O2={2*Xa}CO+{2*Xb}CO2
>> Cu+HNO3=Cu(NO3)2+NO+NO2+H2O
{-Xa+3*Xb}Cu+{8*Xb}HNO3={-Xa+3*Xb}Cu(NO3)2+{-2*Xa+2*Xb}NO+{4*Xa}NO2+{4*Xb}H2O

In this example, 'Xa' and 'Xb' are variables. You can do substitution by assigning values to them.

Hydrates

Hydrate molecules are supported. Use "." to describe hydrate dots. For example:

>> CuSO4.5H2O=CuSO4+H2O
CuSO4.5H2O=CuSO4+5H2O
>> LiOH+H2O2+H2O=Li2O2.H2O2.3H2O
2LiOH+2H2O2+H2O=Li2O2.H2O2.3H2O

Abbreviations

In hand writing, we always use abbreviations such as Et, Ph and Ac. In BCE, you can also use abbreviations. Just surround the abbreviation with "[" and "]". For example:

>> [Et]OH+O2=CO2+H2O
[Et]OH+3O2=2CO2+3H2O

For all supported abbreviations, please open Abbreviation Reference.

Variables and expressions

You can use expressions and variables in your chemical equation. For example:

>> C{n}H{2n+2}+O2=CO2+H2O
{(n+1)^(-1)}C{n}H{2*n+2}+{(1/2)*(3*n+1)/(n+1)}O2={n/(n+1)}CO2+H2O
>> CH3(CHCH){n}CH3+Cl2=CH3(CHClCHCl){n}CH3
CH3(CHCH){n}CH3+{n}Cl2=CH3(CHClCHCl){n}CH3
>> X-<e->=X<{n}e+>
X-{n}<e->=X<{n}e+>

One thing that you may need to pay attention to is that the first letter of the variables you use can't be 'X'. Variables start with 'X' are reserved by the program.

In one expression, you can use operators "+", "-", "*", "/" and "^" ("^" means power, such as 2^3=8). You can also use functions listed in following table:

Function Description
sqrt(x) The square root of variable 'x'.
pow(x,y) Equals to x^y.

Automatic side arranging

If you get several substances and you don't know which are reactants and which are products, you can use ";" to separate each substance and type them to BCE. The program will help you decide the reactants and the products. For example:

>> NH4Cl;K2(HgI4);KCl;KI;H2O;Hg2NH2OI;KOH
NH4Cl+2K2(HgI4)+4KOH=KCl+7KI+3H2O+Hg2NH2OI

We have to acknowledge that the solving algorithm has some limitations. Currently, the algorithm can't decide the reaction direction precisely. You may have to decide it yourself. For example:

>> CH4;HCN;NH3;O2;H2O
2HCN+6H2O=2CH4+2NH3+3O2

The correction result should be:

2CH4+2NH3+3O2=2HCN+6H2O

To avoid this condition, you can specify the status of each substance by adding "(g)", "(l)", "(s)", "(aq)" at the end to let the program guess the reaction direction. For example.

>> CH4(g);HCN(g);NH3(g);O2(g);H2O(g)
2CH4(g)+2NH3(g)+3O2(g)=2HCN(g)+6H2O(g)

It is correct now.

Also, the program can't balance the equation if it has multi solutions. The program will report a logic error in such condition. For example:

>> C;CO2;CO;O2
A logic error occurred (Code: LE.BCE.SIDE_ELIMINATED):

Description:

    Can't balance chemical equations (with auto-correction form) that have multiple answers.

Clone this wiki locally