// Numbas version: exam_results_page_options
{"name": "Moles of a substance 2", "extensions": [], "custom_part_types": [], "resources": [], "navigation": {"allowregen": true, "showfrontpage": false, "preventleave": false, "typeendtoleave": false}, "question_groups": [{"pickingStrategy": "all-ordered", "questions": [{"tags": ["mole", "molecular mass", "Molecular mass", "molecular weight", "Molecular weight", "moles", "RMM"], "metadata": {"description": "<p>Calculate the number of moles in a given mass of a substance given the molecular weight.</p>", "licence": "Creative Commons Attribution 4.0 International"}, "statement": "<p>Answer the following questions. Please enter your answers as decimals, not as fractions. Give your answers to 2 decimal places.</p>\n<p>If you would like to see how to do this question, click on 'Reveal answers' at the bottom of the page.</p>", "variable_groups": [], "name": "Moles of a substance 2", "advice": "<p>To answer these questions we use the formula</p>\n<p style=\"text-align: center;\">$\\dfrac{\\text{mass of substance (in grams)}}{\\text{molecular weight}} = \\text{number of moles}$.</p>\n<p style=\"text-align: left;\">a)</p>\n<p style=\"text-align: left;\">Glucose has a molecular weight of $\\var{glucose}$. How many moles of glucose are there in $\\var{5 * a}$ grams?</p>\n<p style=\"text-align: left;\">Solution:</p>\n<p style=\"text-align: left;\">Putting our numbers into the formula we find that there are&nbsp;</p>\n<p style=\"text-align: center;\">$\\begin{align} \\dfrac{\\var{5 * a}}{\\var{glucose}} &amp;= \\var{(5 * a) / glucose} \\text{ moles}\\\\ &amp;=&nbsp;\\var{precround(((5 * a) / glucose), 2)} \\text{ moles to 2 d.p.} \\end{align}$&nbsp;</p>\n<p style=\"text-align: left;\">in $\\var{5 * a}$ grams of glucose.</p>\n<p style=\"text-align: left;\">b)</p>\n<p style=\"text-align: left;\">Sodium chloride has a molecular weight of $\\var{NaCl}$. How many moles of sodium chloride are there in $\\var{5 * b}$ grams?</p>\n<p style=\"text-align: left;\">Solution:</p>\n<p style=\"text-align: left;\">Putting our numbers into the formula we find that there are</p>\n<p style=\"text-align: center;\">$\\begin{align}\\dfrac{\\var{5 * b}}{\\var{NaCl}} &amp;= \\var{(5 * b) / NaCl} \\text{ moles} \\\\ &amp; = \\var{precround(((5 * b) / NaCl), 2)} \\text{ moles to 2 d.p.} \\end{align}$.</p>\n<p style=\"text-align: left;\">in $\\var{5 * b}$ grams of sodium chloride.</p>", "functions": {}, "rulesets": {}, "variablesTest": {"condition": "", "maxRuns": 100}, "extensions": [], "parts": [{"prompt": "<p>Glucose has a molecular weight of $\\var{glucose}$. How many moles of glucose are there in $\\var{5 * a}$ grams?</p>\n<p>[[0]] moles</p>", "showCorrectAnswer": true, "showFeedbackIcon": true, "type": "gapfill", "variableReplacements": [], "scripts": {}, "marks": 0, "variableReplacementStrategy": "originalfirst", "gaps": [{"notationStyles": ["plain", "en", "si-en"], "showFeedbackIcon": true, "mustBeReducedPC": 0, "mustBeReduced": false, "variableReplacements": [], "allowFractions": false, "showCorrectAnswer": true, "correctAnswerStyle": "plain", "correctAnswerFraction": false, "maxValue": "((5 * a) / glucose) + 0.005", "type": "numberentry", "variableReplacementStrategy": "originalfirst", "minValue": "((5 * a) / glucose) - 0.005", "scripts": {}, "marks": 1}]}, {"prompt": "<p>Sodium chloride has a molecular weight of $\\var{NaCl}$. How many moles of sodium chloride are there in $\\var{5 * b}$ grams?</p>\n<p>[[0]] moles</p>", "showCorrectAnswer": true, "showFeedbackIcon": true, "type": "gapfill", "variableReplacements": [], "scripts": {}, "marks": 0, "variableReplacementStrategy": "originalfirst", "gaps": [{"notationStyles": ["plain", "en", "si-en"], "showFeedbackIcon": true, "mustBeReducedPC": 0, "mustBeReduced": false, "variableReplacements": [], "allowFractions": false, "showCorrectAnswer": true, "correctAnswerStyle": "plain", "correctAnswerFraction": false, "maxValue": "((5 * b) / NaCl) +0.005 ", "type": "numberentry", "variableReplacementStrategy": "originalfirst", "minValue": "((5 * b) / NaCl) - 0.005", "scripts": {}, "marks": 1}]}], "variables": {"b": {"group": "Ungrouped variables", "description": "", "templateType": "anything", "name": "b", "definition": "random(20..40)"}, "a": {"group": "Ungrouped variables", "description": "", "templateType": "anything", "name": "a", "definition": "random(4..20)"}, "glucose": {"group": "Ungrouped variables", "description": "<p>molecular weight of glucose</p>", "templateType": "anything", "name": "glucose", "definition": "180.16"}, "NaCl": {"group": "Ungrouped variables", "description": "<p>molecular weight of sodium chloride</p>", "templateType": "anything", "name": "NaCl", "definition": "58.44"}}, "ungrouped_variables": ["a", "NaCl", "b", "glucose"], "preamble": {"css": "", "js": ""}, "type": "question", "contributors": [{"name": "Jamie Antoun", "profile_url": "https://numbas.mathcentre.ac.uk/accounts/profile/266/"}]}]}], "contributors": [{"name": "Jamie Antoun", "profile_url": "https://numbas.mathcentre.ac.uk/accounts/profile/266/"}]}