Quiz — 63d529928f941_énoncé_Série pH des solutions aqueuses (2).pdf

Question 1 sur 10 20:00

[{"id":24994,"question":"Quel est le pH d'une solution dont la concentration en ions H\u003Csub\u003E3\u003C\/sub\u003EO\u003Csup\u003E+\u003C\/sup\u003E est 10\u003Csup\u003E-3\u003C\/sup\u003E mol\/L ?","option_a":"1","option_b":"3","option_c":"5","option_d":"7","option_e":"","option_f":"","bonne_reponse":"b","explication":"Le pH se calcule par la formule pH = -log[H\u003Csub\u003E3\u003C\/sub\u003EO\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\": \"b\", \"options\": {\"a\": \"1\", \"b\": \"3\", \"c\": \"5\", \"d\": \"7\"}}","_debug_options_count":4},{"id":24995,"question":"Une solution de pH = 8 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 supérieur à 7 indique une solution basique. pH = 8 \u003E 7, donc la solution est 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":24996,"question":"Quelle est la formule du pH pour une solution basique ?","option_a":"pH = -log[H\u003Csub\u003E3\u003C\/sub\u003EO\u003Csup\u003E+\u003C\/sup\u003E]","option_b":"pH = 14 + log[OH\u003Csup\u003E-\u003C\/sup\u003E]","option_c":"pH = -log[OH\u003Csup\u003E-\u003C\/sup\u003E]","option_d":"pH = 14 - pOH","option_e":"","option_f":"","bonne_reponse":"d","explication":"Pour une solution basique, on utilise souvent pH = 14 - pOH, où pOH = -log[OH\u003Csup\u003E-\u003C\/sup\u003E].","points":1,"type":"qcm","actif":1,"section_id":null,"ordre":0,"_debug_answer_data_type":"string","_debug_answer_data_preview":"{\"correct\": \"d\", \"options\": {\"a\": \"pH = -log[H\u003Csub\u003E3\u003C\/sub\u003EO\u003Csup\u003E+\u003C\/sup\u003E]\", \"b\": \"pH = 14 + log[OH\u003Csu","_debug_options_count":4},{"id":24997,"question":"Une solution de pH = 7 est-elle toujours neutre ?","option_a":"Vrai","option_b":"Faux","option_c":"","option_d":"","option_e":"","option_f":"","bonne_reponse":"a","explication":"Un pH = 7 indique une solution neutre uniquement à 25°C. À d'autres températures, le pH de neutralité peut varier.","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":24998,"question":"Quel est le pH d'une solution de soude (NaOH) de concentration 0,01 mol\/L ?","option_a":"2","option_b":"7","option_c":"12","option_d":"14","option_e":"","option_f":"","bonne_reponse":"c","explication":"NaOH est une base forte qui se dissocie totalement. [OH\u003Csup\u003E-\u003C\/sup\u003E] = 0,01 mol\/L, donc pOH = 2 et pH = 14 - 2 = 12.","points":1,"type":"qcm","actif":1,"section_id":null,"ordre":0,"_debug_answer_data_type":"string","_debug_answer_data_preview":"{\"correct\": \"c\", \"options\": {\"a\": \"2\", \"b\": \"7\", \"c\": \"12\", \"d\": \"14\"}}","_debug_options_count":4},{"id":24999,"question":"La réaction entre un acide et une base produit toujours de l'eau et un sel.","option_a":"Vrai","option_b":"Faux","option_c":"","option_d":"","option_e":"","option_f":"","bonne_reponse":"a","explication":"La réaction de neutralisation entre un acide et une base produit généralement de l'eau et un sel, mais ce n'est pas toujours le cas (exemple : réactions avec des oxydes).","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":25000,"question":"Quel est le pH d'une solution de vinaigre (acide acétique CH\u003Csub\u003E3\u003C\/sub\u003ECOOH) de concentration 0,1 mol\/L ?","option_a":"1","option_b":"3","option_c":"5","option_d":"7","option_e":"","option_f":"","bonne_reponse":"c","explication":"L'acide acétique est un acide faible. Son pH se calcule en tenant compte de son pKa (environ 4,75) et de sa concentration. Le pH sera légèrement inférieur 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\": \"3\", \"c\": \"5\", \"d\": \"7\"}}","_debug_options_count":4},{"id":25001,"question":"Dans une solution neutre à 25°C, les concentrations en H\u003Csub\u003E3\u003C\/sub\u003EO\u003Csup\u003E+\u003C\/sup\u003E et OH\u003Csup\u003E-\u003C\/sup\u003E sont égales.","option_a":"Vrai","option_b":"Faux","option_c":"","option_d":"","option_e":"","option_f":"","bonne_reponse":"a","explication":"Dans une solution neutre à 25°C, [H\u003Csub\u003E3\u003C\/sub\u003EO\u003Csup\u003E+\u003C\/sup\u003E] = [OH\u003Csup\u003E-\u003C\/sup\u003E] = 10\u003Csup\u003E-7\u003C\/sup\u003E mol\/L. Leurs concentrations sont donc égales.","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":25002,"question":"Quel est le pH d'une solution de HCl de concentration 0,001 mol\/L ?","option_a":"2","option_b":"3","option_c":"4","option_d":"5","option_e":"","option_f":"","bonne_reponse":"b","explication":"HCl est un acide fort qui se dissocie totalement. [H\u003Csub\u003E3\u003C\/sub\u003EO\u003Csup\u003E+\u003C\/sup\u003E] = 0,001 mol\/L, donc pH = -log(0,001) = 3.","points":1,"type":"qcm","actif":1,"section_id":null,"ordre":0,"_debug_answer_data_type":"string","_debug_answer_data_preview":"{\"correct\": \"b\", \"options\": {\"a\": \"2\", \"b\": \"3\", \"c\": \"4\", \"d\": \"5\"}}","_debug_options_count":4},{"id":25003,"question":"Le pH d'une solution peut-il être négatif ?","option_a":"Vrai","option_b":"Faux","option_c":"","option_d":"","option_e":"","option_f":"","bonne_reponse":"a","explication":"Oui, le pH peut être négatif pour des solutions très concentrées en ions H\u003Csub\u003E3\u003C\/sub\u003EO\u003Csup\u003E+\u003C\/sup\u003E (exemple : pH = -1 pour [H\u003Csub\u003E3\u003C\/sub\u003EO\u003Csup\u003E+\u003C\/sup\u003E] = 10 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\": \"Vrai\", \"b\": \"Faux\", \"c\": \"\", \"d\": \"\"}}","_debug_options_count":4}]