Quiz — 63d52d674699b_énoncé_pH des solutions aqueuses_Série_2 (2).pdf

Question 1 sur 10 20:00

[{"id":11503,"question":"Quel est le pH d'une solution neutre ?","option_a":"0","option_b":"7","option_c":"14","option_d":"10","option_e":"","option_f":"","bonne_reponse":"b","explication":"Une solution neutre a un pH de 7, ce qui signifie qu'elle contient autant d'ions H+ que d'ions OH-.","points":1,"type":"qcm","actif":1,"section_id":null,"ordre":0,"_debug_answer_data_type":"string","_debug_answer_data_preview":"{\"correct\": \"b\", \"options\": {\"a\": \"0\", \"b\": \"7\", \"c\": \"14\", \"d\": \"10\"}}","_debug_options_count":4},{"id":11504,"question":"Un indicateur coloré est une substance qui change de couleur en fonction du pH de la solution.","option_a":"Vrai","option_b":"Faux","option_c":"","option_d":"","option_e":"","option_f":"","bonne_reponse":"a","explication":"C'est exact : un indicateur coloré est une substance dont la couleur dépend du pH de la solution dans laquelle il est introduit.","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":11505,"question":"Quelle est la formule permettant de calculer le pH d'une solution d'acide fort de concentration C ?","option_a":"pH = -log(C)","option_b":"pH = log(C)","option_c":"pH = 14 + log(C)","option_d":"pH = -log(C\/10)","option_e":"","option_f":"","bonne_reponse":"a","explication":"Pour un acide fort, le pH se calcule avec la formule pH = -log(C), où C est la concentration en ions H+ (égale à la concentration de l'acide pour un acide fort).","points":1,"type":"qcm","actif":1,"section_id":null,"ordre":0,"_debug_answer_data_type":"string","_debug_answer_data_preview":"{\"correct\": \"a\", \"options\": {\"a\": \"pH = -log(C)\", \"b\": \"pH = log(C)\", \"c\": \"pH = 14 + log(C)\", \"d\": ","_debug_options_count":4},{"id":11506,"question":"Une solution a un pH de 3. Comment peut-on la qualifier ?","option_a":"Acide","option_b":"Basique","option_c":"Neutre","option_d":"Amphotère","option_e":"","option_f":"","bonne_reponse":"a","explication":"Un pH de 3 est inférieur à 7, donc la solution est acide.","points":1,"type":"qcm","actif":1,"section_id":null,"ordre":0,"_debug_answer_data_type":"string","_debug_answer_data_preview":"{\"correct\": \"a\", \"options\": {\"a\": \"Acide\", \"b\": \"Basique\", \"c\": \"Neutre\", \"d\": \"Amphotère\"}}","_debug_options_count":4},{"id":11507,"question":"Lors d'une réaction acido-basique, les ions H+ réagissent avec les ions OH- pour former :","option_a":"De l'eau (H2O)","option_b":"Du dioxyde de carbone (CO2)","option_c":"Du sel (NaCl)","option_d":"De l'oxygène (O2)","option_e":"","option_f":"","bonne_reponse":"a","explication":"La réaction entre H+ et OH- donne de l'eau (H2O), c'est la réaction de neutralisation.","points":1,"type":"qcm","actif":1,"section_id":null,"ordre":0,"_debug_answer_data_type":"string","_debug_answer_data_preview":"{\"correct\": \"a\", \"options\": {\"a\": \"De l'eau (H2O)\", \"b\": \"Du dioxyde de carbone (CO2)\", \"c\": \"Du sel","_debug_options_count":4},{"id":11508,"question":"Le papier pH permet de mesurer le pH avec une grande précision.","option_a":"Vrai","option_b":"Faux","option_c":"","option_d":"","option_e":"","option_f":"","bonne_reponse":"b","explication":"Le papier pH donne une estimation du pH, mais il est moins précis qu'un pH-mètre électronique.","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":11509,"question":"Quel est le pH d'une solution de soude (NaOH) de concentration 10^-2 mol\/L ?","option_a":"2","option_b":"10","option_c":"12","option_d":"14","option_e":"","option_f":"","bonne_reponse":"c","explication":"La soude est une base forte. Pour une base forte, pH = 14 + log(C) = 14 + log(10^-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\": \"10\", \"c\": \"12\", \"d\": \"14\"}}","_debug_options_count":4},{"id":11510,"question":"Lors d'une dilution, le pH d'une solution acide :","option_a":"Augmente","option_b":"Diminue","option_c":"Reste inchangé","option_d":"Devient basique","option_e":"","option_f":"","bonne_reponse":"a","explication":"Diluer une solution acide réduit sa concentration en ions H+, donc son pH augmente (mais reste inférieur à 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\": \"Augmente\", \"b\": \"Diminue\", \"c\": \"Reste inchangé\", \"d\": \"Devient ","_debug_options_count":4},{"id":11511,"question":"Un dosage acido-basique permet de déterminer :","option_a":"La couleur de la solution","option_b":"La concentration d'une solution acide ou basique","option_c":"Le volume de la solution","option_d":"La température de la solution","option_e":"","option_f":"","bonne_reponse":"b","explication":"Un dosage acido-basique permet de déterminer la concentration inconnue d'une solution acide ou basique en la neutralisant avec une solution de concentration connue.","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 solution","_debug_options_count":4},{"id":11512,"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, pour des solutions très concentrées en acide fort, le pH peut être négatif (ex. : pH = -1 pour une solution de HCl à 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}]