ChemicalReaction1

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Chemical Reactions

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This PG code shows how ask questions about chemical reactions.

• PGML location in OPL: FortLewis/Authoring/Templates/Misc/ChemicalReaction1_PGML.pg

Templates by Subject Area

PG problem file	Explanation
Problem tagging data	Problem tagging:
DOCUMENT(); loadMacros( "PGstandard.pl", "PGunion.pl", "MathObjects.pl", "PGML.pl", "contextReaction.pl", "PGcourse.pl", ); TEXT(beginproblem()); # uncomment $showPartialCorrectAnswers = 1;	Initialization: Load contextReaction.pl.
Context("Reaction"); @reactants = (); @products = (); $reactants[0] = Formula("2C_2H_6 + 7O_2"); $products[0] = Formula("4CO_2 + 6H_2O"); $reactants[1] = Formula("6CO_2 + 6O_2"); $products[1] = Formula("C_6 H_12 O_6 + 6 O_2"); $reactants[2] = Formula("3 Ca Cl_2 + 2 Na_3 PO_4"); $products[2] = Formula("Ca_3 (PO_4)_2 + 6 Na Cl"); # variations on 2NaOH + MgCl_2 --> 2NaCl + Mg(OH)_2 $a = list_random('Li','Na','K'); $b = list_random('F','Cl','Br'); # Use ${b}_2 instead of $b_2 below so that Perl knows the # variable name is $b = ${b} and not $b_2 = ${b_2}. $reactants[3] = Formula("2 $a OH + Mg ${b}_2"); $products[3] = Formula("2 $a $b + Mg (OH)_2"); $num_choices = $#reactants; $i = random(0,$num_choices,1);	Setup: We create a couple of arrays @reactants and @products and fill them with some examples of balanced chemical equations. The second and third examples show that groupings, such as for (OH)_2 are necessary. The third example shows how you could randomize a chemical reaction question. In particular, note that ${b}_2 is needed instead of $b_2 so that Perl interprets the variable as $b with a subscript of 2 instead of a variable named $b_2 with no subscript.
BEGIN_PGML [` [$reactants[ $i ]] \longrightarrow `] [_____________________________]{$products[ $i ]} Enter a subscript using an underscore, such as [| H_2 O |]* for [` \mathrm{H_2 O} `]. END_PGML COMMENT('MathObject version. Uses PGML.'); ENDDOCUMENT();	Main Text: Note that we uses spaces around $i in things like $reactants[ $i ] and $products[ $i ]. This is a work around for a known PGML bug as of June 2015 (the bug will likely get fixed very soon).

Templates by Subject Area

• POD documentation for contextReaction.pl
• WeBWorK forum discussion about chemical reactions