Which of the following can only be separated into two or more pure substances by a chemical change?

a. an element

b. a compound

c. a homogeneous mixture

d. a heterogeneous mixture

If you were asked to convert 4.2 * 1022 atoms of aluminum to moles, which of the following should you use for the conversion?

A 1.85 mass % aqueous solution urea (CO (NH2) 2) has a density of 1.05 g/mL. Calculate the molality of the solution. Give your answer to 2 decimal places.

Why will nuclear fission probably never be used directly for powering automobiles?

Fire is combination of what? example (water is a compound of hydrogen and oxygen)

Which of the following shows three elements in order of decreasing conductivity? A. Zn, Pd, Ag B. Pd, Ag, Zn C. Ag, Pd, Zn D. Zn, Ag, Pd Which of the following is the name of a metal? A. K B. Potassium chloride C. Potassium D. KCI

Why do airbags fill evenly with gases?

In which of the following reactions will Kc = Kp? In which of the following reactions will Kc = Kp? (A) SO3 (g) + NO (g) ↔ SO2 (g) + NO2 (g) (B) 2 N2 (g) + O2 (g) ↔ 2 N2O (g) (C) 4 NH3 (g) + 3 O2 (g) ↔ 2 N2 (g) + 6 H2O (g) (D) 2 SO2 (g) + O2 (g) ↔ 2

Which tool is most suitable for a chemist to measure the mass of a liquid

What is the equation adheres to the law of conservation of matter

What ironic contrast does Vonnegut include in this scene? George tells his wife to forget sad things, but readers would expect George and Hazel to want to remember their son.