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(07.05 MC) When a cube of manganese oxide was added to a solution of hydrogen peroxide, water and oxygen were produced. Manganese oxide was not used up in the reaction. Which of the following is likely to decrease the rate of the reaction?

(08.02 MC) A 0.0300 M NaCl solution was formed when 42.0 grams of NaCl was dissolved in enough water. What was the total volume of the solution formed?

Completar. Fill in the blanks with the appropriate words. Two words will not be used. (4 x 1 pt. each = 4 pts.) —Alberto, ¿[1] es la clase de matemáticas?—Es a las 2 de la tarde. —¿[2] son tus clases favoritas?—Matemáticas y ciencias. —¿[3] viajan ustedes?—Viajamos a Puerto Rico. —¿[4] hay tres laboratorios?—Hay tres porque muchos estudiantes estudian química.

(06.03 LC) Which of the following most likely happens when the volume of a gas increases?

(06.04 HC) During a laboratory experiment, 44.18 grams of Al2O3 was formed when O2 reacted with aluminum metal at 290.0 K and 1.3 atm. What was the volume of O2 used during the experiment?3O2 + 4Al → 2Al2O3

(07.01 MC) A student made a sketch of a potential energy diagram to represent a reaction with a −ΔH value.Explain, using complete sentences, why the diagram made by the student is correct or incorrect. Be sure to also explain what the values of X and Y represent.

(07.06 MC) A student made a graph to show chemical equilibrium position of a reaction. The student forgot to label the y-axis of the graph.What best explains the label that the student should use on the y-axis?

Cultura. Select the correct answer for each question. (7 x 1 pt. Each = 7 pts) La población de España es de aproximadamente:[1] España no tiene frontera (border) con:[2] El español es una lengua oficial en España. Otra lengua oficial en este país es:[3] El Prado es un ______ importante.[4] Un escritor (writer) español famoso es:[5] Un plato típico de España que se prepara con arroz (rice) y azafrán (safron) se llama:[6] La moneda de España es:[7]

A 45-year-old female patient complains of nausea, vomiting, fatigue, and weakness. She admits to a history of heroin abuse for 11 years. She quit using the drug after rehabilitation last year and denies current use of the drug. Habits include use of alcohol (four to five drinks daily) and tobacco use of 60-pack years. On physical examination, she is afebrile, has a blood pressure of 148/98, pulse 78 beat/min, and respirations 16 breaths/min. The patient has periorbital edema. Lungs are clear to auscultation. Abdomen is nontender and distended with mild hepatomegaly. No neurological deficits. Laboratory testing reveals Hgb 10, BUN 60, potassium 6.1, and serum creatinine 2.9 mg/dL. These findings are characteristic of:

(08.04 LC) Which statement is true about a substance that has a pH value of 14?