Quiz — 51.._serie 1 pH.pdf

Question 1 sur 10 20:00

[{"id":37980,"question":"Quel est le pH d'une solution de concentration [H\u003Csup\u003E+\u003C\/sup\u003E] = 10\u003Csup\u003E-3\u003C\/sup\u003E mol\/L ?","option_a":"3","option_b":"11","option_c":"7","option_d":"14","option_e":"","option_f":"","bonne_reponse":"a","explication":"Le pH se calcule par la formule pH = -log[H\u003Csup\u003E+\u003C\/sup\u003E]. Ici, pH = -log(10\u003Csup\u003E-3\u003C\/sup\u003E) = 3.","points":1,"type":"qcm","actif":1,"section_id":null,"ordre":0,"_debug_answer_data_type":"string","_debug_answer_data_preview":"{\"correct\": \"a\", \"options\": {\"a\": \"3\", \"b\": \"11\", \"c\": \"7\", \"d\": \"14\"}}","_debug_options_count":4},{"id":37981,"question":"Une solution de pH = 9 est-elle acide, basique ou neutre ?","option_a":"Vrai","option_b":"Faux","option_c":"","option_d":"","option_e":"","option_f":"","bonne_reponse":"b","explication":"Un pH \u003E 7 indique une solution basique. pH = 9 \u003E 7, donc basique.","points":1,"type":"qcm","actif":1,"section_id":null,"ordre":0,"_debug_answer_data_type":"string","_debug_answer_data_preview":"{\"correct\": \"b\", \"options\": {\"a\": \"Vrai\", \"b\": \"Faux\", \"c\": \"\", \"d\": \"\"}}","_debug_options_count":4},{"id":37982,"question":"Quel indicateur coloré est utilisé pour un pH entre 8,2 et 10 ?","option_a":"Bleu de bromophénol","option_b":"Phénolphtaléine","option_c":"Rouge de méthyle","option_d":"Vert de bromocrésol","option_e":"","option_f":"","bonne_reponse":"b","explication":"La phénolphtaléine change de couleur entre pH 8,2 (incolore) et pH 10 (rose).","points":1,"type":"qcm","actif":1,"section_id":null,"ordre":0,"_debug_answer_data_type":"string","_debug_answer_data_preview":"{\"correct\": \"b\", \"options\": {\"a\": \"Bleu de bromophénol\", \"b\": \"Phénolphtaléine\", \"c\": \"Rouge de m","_debug_options_count":4},{"id":37983,"question":"Si [OH\u003Csup\u003E-\u003C\/sup\u003E] = 10\u003Csup\u003E-4\u003C\/sup\u003E mol\/L, quel est le pH de la solution ?","option_a":"4","option_b":"10","option_c":"7","option_d":"14","option_e":"","option_f":"","bonne_reponse":"b","explication":"pH + pOH = 14. pOH = -log[OH\u003Csup\u003E-\u003C\/sup\u003E] = 4, donc pH = 14 - 4 = 10.","points":1,"type":"qcm","actif":1,"section_id":null,"ordre":0,"_debug_answer_data_type":"string","_debug_answer_data_preview":"{\"correct\": \"b\", \"options\": {\"a\": \"4\", \"b\": \"10\", \"c\": \"7\", \"d\": \"14\"}}","_debug_options_count":4},{"id":37984,"question":"Le pH d'une solution augmente-t-il si on y ajoute de l'eau distillée ?","option_a":"Vrai","option_b":"Faux","option_c":"","option_d":"","option_e":"","option_f":"","bonne_reponse":"a","explication":"Diluer une solution acide ou basique rapproche son pH de 7, donc le pH augmente si la solution était acide (pH \u003C 7).","points":1,"type":"qcm","actif":1,"section_id":null,"ordre":0,"_debug_answer_data_type":"string","_debug_answer_data_preview":"{\"correct\": \"a\", \"options\": {\"a\": \"Vrai\", \"b\": \"Faux\", \"c\": \"\", \"d\": \"\"}}","_debug_options_count":4},{"id":37985,"question":"Quelle est la concentration en ions H\u003Csup\u003E+\u003C\/sup\u003E d'une solution de pH = 2 ?","option_a":"10\u003Csup\u003E-2\u003C\/sup\u003E mol\/L","option_b":"2 mol\/L","option_c":"10\u003Csup\u003E-12\u003C\/sup\u003E mol\/L","option_d":"10\u003Csup\u003E2\u003C\/sup\u003E mol\/L","option_e":"","option_f":"","bonne_reponse":"a","explication":"[H\u003Csup\u003E+\u003C\/sup\u003E] = 10\u003Csup\u003E-pH\u003C\/sup\u003E = 10\u003Csup\u003E-2\u003C\/sup\u003E mol\/L.","points":1,"type":"qcm","actif":1,"section_id":null,"ordre":0,"_debug_answer_data_type":"string","_debug_answer_data_preview":"{\"correct\": \"a\", \"options\": {\"a\": \"10\u003Csup\u003E-2\u003C\/sup\u003E mol\/L\", \"b\": \"2 mol\/L\", \"c\": \"10\u003Csup\u003E-12\u003C\/sup\u003E mo","_debug_options_count":4},{"id":37986,"question":"Un dosage acido-basique permet de déterminer :","option_a":"La couleur de la solution","option_b":"La concentration d'une espèce chimique","option_c":"La masse molaire","option_d":"Le volume de la solution","option_e":"","option_f":"","bonne_reponse":"b","explication":"Un dosage acido-basique sert à déterminer la concentration d'un acide ou d'une base dans une solution.","points":1,"type":"qcm","actif":1,"section_id":null,"ordre":0,"_debug_answer_data_type":"string","_debug_answer_data_preview":"{\"correct\": \"b\", \"options\": {\"a\": \"La couleur de la solution\", \"b\": \"La concentration d'une espèce ","_debug_options_count":4},{"id":37987,"question":"Le pH d'une solution de soude (NaOH) concentrée est toujours supérieur à 7.","option_a":"Vrai","option_b":"Faux","option_c":"","option_d":"","option_e":"","option_f":"","bonne_reponse":"a","explication":"La soude est une base forte, donc son pH est toujours \u003E 7.","points":1,"type":"qcm","actif":1,"section_id":null,"ordre":0,"_debug_answer_data_type":"string","_debug_answer_data_preview":"{\"correct\": \"a\", \"options\": {\"a\": \"Vrai\", \"b\": \"Faux\", \"c\": \"\", \"d\": \"\"}}","_debug_options_count":4},{"id":37988,"question":"Quelle est la formule reliant pH et concentration en ions H\u003Csup\u003E+\u003C\/sup\u003E ?","option_a":"pH = [H\u003Csup\u003E+\u003C\/sup\u003E]","option_b":"pH = -log[H\u003Csup\u003E+\u003C\/sup\u003E]","option_c":"pH = 1\/[H\u003Csup\u003E+\u003C\/sup\u003E]","option_d":"[H\u003Csup\u003E+\u003C\/sup\u003E] = 10\u003Csup\u003EpH\u003C\/sup\u003E","option_e":"","option_f":"","bonne_reponse":"b","explication":"La formule correcte est pH = -log[H\u003Csup\u003E+\u003C\/sup\u003E], où [H\u003Csup\u003E+\u003C\/sup\u003E] est en mol\/L.","points":1,"type":"qcm","actif":1,"section_id":null,"ordre":0,"_debug_answer_data_type":"string","_debug_answer_data_preview":"{\"correct\": \"b\", \"options\": {\"a\": \"pH = [H\u003Csup\u003E+\u003C\/sup\u003E]\", \"b\": \"pH = -log[H\u003Csup\u003E+\u003C\/sup\u003E]\", \"c\": \"pH ","_debug_options_count":4},{"id":37989,"question":"Si on mélange 50 mL d'une solution de pH = 2 avec 50 mL d'eau, quel est le nouveau pH ?","option_a":"1","option_b":"2","option_c":"3","option_d":"4","option_e":"","option_f":"","bonne_reponse":"c","explication":"La dilution divise [H\u003Csup\u003E+\u003C\/sup\u003E] par 2 : [H\u003Csup\u003E+\u003C\/sup\u003E] = 5×10\u003Csup\u003E-3\u003C\/sup\u003E mol\/L, donc pH = -log(5×10\u003Csup\u003E-3\u003C\/sup\u003E) ≈ 2,3 → arrondi à 3.","points":1,"type":"qcm","actif":1,"section_id":null,"ordre":0,"_debug_answer_data_type":"string","_debug_answer_data_preview":"{\"correct\": \"c\", \"options\": {\"a\": \"1\", \"b\": \"2\", \"c\": \"3\", \"d\": \"4\"}}","_debug_options_count":4}]