Find the standard enthalpy of formation of ethylene, C2H4(g), given the following data: heat of combustion of C2H4(g)= –1411 kJ/mol; ΔH°f[CO2(g)] = –393.5 kJ/mol; ΔH°f[H2O(l)] = –285.8 kJ/mol. *HINT the reaction for combustion is: fuel reacts with oxygen gas to form carbon dioxide and water – write and balance the equation.
Read DetailsA 68-year-old woman with hypertension, type 2 diabetes mellitus, and hyperlipidemia presents for psychiatric evaluation on referral from the emergency department, where she has presented six times in the last year because of her concern that she has pancreatic cancer. She reports generalized abdominal discomfort that “comes and goes.” A thorough medical workup, including imaging and evaluation by a gastroenterologist, is negative. She is anxious and complains of poor sleep due to her concerns about her health. She has no other psychiatric symptoms or prior history. Which of the following somatic symptom and related disorders is the most likely diagnosis?
Read DetailsAn 85-year-old man comes to your office with concerns that his family has noticed changes in his sleep pattern. His grandson complains that he goes to bed too early, and his daytime napping worries his daughter. The patient admits that he is more tired than he used to be and he goes to bed and wakes up earlier than in the past. Which statement most adequately addresses the concerns of this patient?
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