Quiz — Lycée Pilote Bizerte - acide-base + pH 2.pdf

Question 1 sur 5 10:00

[{"id":2363,"question":"Quel est le pH d'une solution d'acide chlorhydrique (HCl) de concentration 0,01 mol\/L ?","option_a":"pH = 2","option_b":"pH = 1","option_c":"pH = 3","option_d":"pH = 0,01","option_e":"","option_f":"","bonne_reponse":"a","explication":"L'acide chlorhydrique est un acide fort qui se dissocie totalement. [H₃O⁺] = 0,01 mol\/L, donc pH = -log(0,01) = 2.","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 = 2\", \"b\": \"pH = 1\", \"c\": \"pH = 3\", \"d\": \"pH = 0,01\"}}","_debug_options_count":4},{"id":2364,"question":"Quelle est la base conjuguée de l'acide acétique (CH₃COOH) ?","option_a":"CH₃COO⁻","option_b":"H₃O⁺","option_c":"OH⁻","option_d":"H₂O","option_e":"","option_f":"","bonne_reponse":"a","explication":"En perdant un proton H⁺, l'acide acétique donne sa base conjuguée : l'ion acétate CH₃COO⁻.","points":1,"type":"qcm","actif":1,"section_id":null,"ordre":0,"_debug_answer_data_type":"string","_debug_answer_data_preview":"{\"correct\": \"a\", \"options\": {\"a\": \"CH₃COO⁻\", \"b\": \"H₃O⁺\", \"c\": \"OH⁻\", \"d\": \"H₂O\"}}","_debug_options_count":4},{"id":2365,"question":"Que vaut le pH d'une solution de soude (NaOH) de concentration 10⁻³ mol\/L ?","option_a":"pH = 3","option_b":"pH = 11","option_c":"pH = 7","option_d":"pH = 14","option_e":"","option_f":"","bonne_reponse":"b","explication":"NaOH est une base forte qui libère OH⁻. [OH⁻] = 10⁻³ mol\/L, donc pOH = 3 et pH = 14 - 3 = 11.","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 = 3\", \"b\": \"pH = 11\", \"c\": \"pH = 7\", \"d\": \"pH = 14\"}}","_debug_options_count":4},{"id":2366,"question":"Lors d'un titrage acido-basique, à quoi correspond le point d'équivalence ?","option_a":"Le moment où le pH est égal à 7","option_b":"Le moment où les réactifs sont en proportions stœchiométriques","option_c":"Le moment où la solution devient colorée","option_d":"Le moment où la réaction est terminée","option_e":"","option_f":"","bonne_reponse":"b","explication":"Le point d'équivalence est atteint lorsque les quantités de matière d'acide et de base mises en jeu sont dans les proportions de l'équation de réaction.","points":1,"type":"qcm","actif":1,"section_id":null,"ordre":0,"_debug_answer_data_type":"string","_debug_answer_data_preview":"{\"correct\": \"b\", \"options\": {\"a\": \"Le moment où le pH est égal à 7\", \"b\": \"Le moment où les réa","_debug_options_count":4},{"id":2367,"question":"Quelle est la formule permettant de calculer le pH d'une solution d'acide faible de concentration C et de constante d'acidité Ka ?","option_a":"pH = -log(C)","option_b":"pH = -log(√(Ka·C))","option_c":"pH = -log(Ka)","option_d":"pH = log(C\/Ka)","option_e":"","option_f":"","bonne_reponse":"b","explication":"Pour un acide faible, [H₃O⁺] ≈ √(Ka·C), donc pH = -log(√(Ka·C)).","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 = -log(C)\", \"b\": \"pH = -log(√(Ka·C))\", \"c\": \"pH = -log(Ka)\"","_debug_options_count":4}]