, and incorrectly identifies the period as 3, likely confused by the $3d^{10}$ term.","order":2},{"id":"3cb1072b-5f63-41cf-b3cd-73f44f26420c","content":"Block: $d$, Group: 5, Period: 4","correct":false,"markscheme":"Incorrect. This distractor mistakes the block as $d$ due to the $3d^{10}$ subshell, and incorrectly identifies the group as Group 5 (the transition metal group with configuration $d^3 s^2$).","order":3}],"explanation":null,"firstAttemptFullMarks":null},{"id":"393c63dd-19c2-4b47-b1ce-0c8e1d9ba421","revisionId":"88dfa394-32eb-4630-b751-898e3f51c20e","questionNumber":null,"questionType":"LA","specification":"","difficulty":2,"difficultyBand":"medium","totalMarks":13,"sourceTitle":null,"calculatorUse":null,"parts":[{"id":"e2d08e22-1b8f-4daa-9030-5472ed097825","label":"a","content":"$3f","markscheme":"- Selects **X** B1\n- States any temperature strictly between $650^\\circ\\text{C}$ and $1090^\\circ\\text{C}$ (e.g., $800^\\circ\\text{C}$) B1\n- Completes the first sentence with **freezing** B1\n- Completes the second sentence with **less** B1\n- Completes the third sentence with **less** B1","marks":5,"order":0,"markingRubric":null,"explanation":null,"options":[]},{"id":"99ebebf9-40dd-4f44-a018-5f38df13e5e2","label":"b","content":"Match each **particle** with its correct **description**:\n\n* **Particles**: proton, electron, neutron\n* **Descriptions**:\n 1. relative charge of \$-1\$ and very small relative mass\n 2. relative charge of \$+1\$ and relative mass of \$1\$\n 3. relative charge of \$0\$ (no charge) and relative mass of \$1\$","markscheme":"- Correctly matches proton with: relative charge of $+1$ and relative mass of $1$ B1\n- Correctly matches electron with: relative charge of $-1$ and very small relative mass B1\n- Correctly matches neutron with: relative charge of $0$ (no charge) and relative mass of $1$ B1","marks":3,"order":1,"markingRubric":null,"explanation":null,"options":[]},{"id":"706c4e18-45ef-4b51-8f0a-922e9fcd3882","label":"c","content":"The element magnesium has three different isotopes:\n\n* Isotope 1: \${}^{24}_{12}\\text{Mg}\$\n* Isotope 2: \${}^{25}_{12}\\text{Mg}\$\n* Isotope 3: \${}^{26}_{12}\\text{Mg}\$\n\n**(i)** Which isotope has the **highest** mass?\n\n**(ii)** Which isotope has the **same number** of protons and neutrons?\n\n**(iii)** Atoms of each isotope have the same number of electrons. How many electrons do these atoms have?","markscheme":"- Identifies Isotope 3 (or ${}^{26}_{12}\\text{Mg}$) B1\n- Identifies Isotope 1 (or ${}^{24}_{12}\\text{Mg}$) B1\n- States that there are $12$ electrons B1","marks":3,"order":2,"markingRubric":null,"explanation":null,"options":[]},{"id":"2deb55bd-b4be-4579-80d0-b62e126f19b0","label":"d","content":"A sample of magnesium contains all three isotopes. It contains \$78.99\\%\$ of isotope 1 and \$10.00\\%\$ of isotope 2.\n\nCalculate the percentage of isotope 3 in the sample of magnesium.","markscheme":"- Sets up the calculation $100\\% - (78.99\\% + 10.00\\%)$ M1\n- Obtains $11.01\\%$ A1","marks":2,"order":3,"markingRubric":null,"explanation":null,"options":[]}],"options":[],"explanation":null,"firstAttemptFullMarks":null}],"subjectCode":"gcse_chemistry__ocr","summaries":[{"id":"016463d9-b122-4f84-b41e-7a7501facc79","difficultyBand":"easy","calculatorUse":null},{"id":"0209569e-2054-4071-9278-7733fb58c577","difficultyBand":"easy","calculatorUse":null},{"id":"062377c3-ea8a-4125-9e2f-2006c00d2425","difficultyBand":"medium","calculatorUse":null},{"id":"08cda15c-a452-47ea-9779-d45322b41f49","difficultyBand":"easy","calculatorUse":null},{"id":"09f57d5e-4870-4800-9291-7cbba91f6643","difficultyBand":"medium","calculatorUse":null},{"id":"0b40f8bd-6796-4a2f-b465-3993d0ef00c5","difficultyBand":"easy","calculatorUse":null},{"id":"0c345618-3e96-4781-9c37-20ead131c936","difficultyBand":"easy","calculatorUse":null},{"id":"0d6c7423-30d4-435c-b

Atomic structure

Question 10

Atomic structure Questions

Atomic structure

Question 10

Atomic structure Questions