ydrogen.](https://assets.mathsgenie.co.uk/aqa-qb/4b9a1135-5b3c-4cf6-94b4-b4b8cd01fa84.png)","difficulty":3,"difficultyBand":"easy","totalMarks":8,"sourceTitle":null,"calculatorUse":null,"parts":[{"id":"fb131dff-f49c-4b5b-ba05-0e1fa621cf5d","label":"a","content":"Complete the table to show the number of atoms of each element in this displayed formula.\n\n| Element | Number of atoms |\n| :---: | :---: |\n| C | ........................ |\n| H | ........................ |\n| O | ........................ |","markscheme":"- Identifies $2$ Carbon ($\\text{C}$) atoms B1\n- Identifies $6$ Hydrogen ($\\text{H}$) atoms B1\n- Identifies $2$ Oxygen ($\\text{O}$) atoms B1","marks":3,"order":0,"markingRubric":null,"explanation":null,"options":[]},{"id":"f4b29ce7-e028-48ed-b234-c5aade45208c","label":"b","content":"What is the **empirical formula** of ethane-1,2-diol?","markscheme":"- Finds the ratio of atoms as $\\text{C}_2\\text{H}_6\\text{O}_2$ and simplifies by dividing by $2$ to get $1 : 3 : 1$ M1\n- States the empirical formula as $\\text{CH}_3\\text{O}$ A1","marks":2,"order":1,"markingRubric":null,"explanation":null,"options":[]},{"id":"b6505124-4127-4aed-965c-c58aa044c020","label":"c","content":"Ethane-1,2-diol has a melting point of \$-13\\ ^\\circ\\text{C}\$ and a boiling point of \$197\\ ^\\circ\\text{C}\$.\n\nWhat is the state of ethane-1,2-diol at \$25\\ ^\\circ\\text{C}\$?\n\nExplain your answer.","markscheme":"- States that the state of ethane-1,2-diol is liquid B1\n- Explains that $25\\ ^\\circ\\text{C}$ is above the melting point of $-13\\ ^\\circ\\text{C}$ B1\n- Explains that $25\\ ^\\circ\\text{C}$ is below the boiling point of $197\\ ^\\circ\\text{C}$ B1","marks":3,"order":2,"markingRubric":null,"explanation":null,"options":[]}],"options":[],"explanation":null,"firstAttemptFullMarks":null}],"subjectCode":"gcse_chemistry__ocr","summaries":[{"id":"016f4f7b-4aec-459f-98a2-28929c7d9921","difficultyBand":"medium","calculatorUse":null},{"id":"0ad9c131-6de3-486c-bbe0-63636a4ca0e0","difficultyBand":"easy","calculatorUse":null},{"id":"0d2ecce0-f35a-4cf1-9d56-536d4cfb09ad","difficultyBand":"easy","calculatorUse":null},{"id":"174a0a05-a675-4e28-bf37-a1513d502d10","difficultyBand":"easy","calculatorUse":null},{"id":"18e140e6-2e75-4e62-8d66-996e432d7244","difficultyBand":"easy","calculatorUse":null},{"id":"2a7cd3f5-761d-4514-95e2-e064affedb8c","difficultyBand":"medium","calculatorUse":null},{"id":"32cec466-b71e-403b-a7ef-2752af6604ec","difficultyBand":"easy","calculatorUse":null},{"id":"36718df6-96cf-41a5-be89-767f1ff1547f","difficultyBand":"easy","calculatorUse":null},{"id":"3b9c049b-906a-4037-8b9c-c6da2ed57e4b","difficultyBand":"easy","calculatorUse":null},{"id":"42555eef-b0d3-482d-ac03-5396ed343ead","difficultyBand":"easy","calculatorUse":null},{"id":"43ce757c-4070-4450-8f4b-204c2a3f875d","difficultyBand":"medium","calculatorUse":null},{"id":"45bab9dd-b348-49d7-b28c-1fe55683cadc","difficultyBand":"medium","calculatorUse":null},{"id":"48a87fe7-8fa5-4568-8df5-6cc4bee710e9","difficultyBand":"easy","calculatorUse":null},{"id":"497045ce-e7b2-4460-8067-661e284f912b","difficultyBand":"medium","calculatorUse":null},{"id":"4beaa34c-2ece-46d0-bfc4-720a4ce6ee84","difficultyBand":"easy","calculatorUse":null},{"id":"53ef458f-b7a0-4b42-bea8-2dd26ab67960","difficultyBand":"easy","calculatorUse":null},{"id":"5418646a-7f94-46c9-8309-921a78d1fbc6","difficultyBand":"easy","calculatorUse":null},{"id":"5ac245a8-70f2-4ef3-8d13-39495202d521","difficultyBand":"easy","calculatorUse":null},{"id":"60abec98-5fdd-4b66-8a4a-7209c4417139","difficultyBand":"easy","calculatorUse":null},{"id":"60af353d-4a9a-4c73-8b95-b8af7e3f204d","difficultyBand":"easy","calculatorUse":null},{"id":"6e813e51-8761-4928-b4b5-c6df0816a028","difficultyBand":"easy","calculatorUse":null},{"id":"753478d6-f851-44f8-9357-29793d034dad","difficultyBand":"easy","calculatorUse":null},{"id":"754ccb96-7f49-432a-9f41-c79aba4d312f","difficultyBand":"easy","calculatorUse"

Introducing chemical reactions

Question 33

Introducing chemical reactions Questions

Introducing chemical reactions

Question 33

Introducing chemical reactions Questions