Which statement is true about oxygen and rocks?

Both are mixtures.

Both are pure substances.

Oxygen is a mixture and a rock is a pure substance.

Oxygen is a pure substance and rocks are mixtures.

Why is respiration an exothermic reaction? A large amount of energy is released into the surroundings. The heat content, q, of the reaction is positive. A large amount of energy is required to activate the reaction.

Which ion will form a basic solution when dissolved in water? hso4-?

How does the number of molecules in 1 mol of oxygen compare with the number of molecules in 1 mol of nitrogen?

In which layer is the pressure the highest A. the inner core B. the outer core C. the crust D. The lower mantle

Why is it called a compound microscop

What happens to the velocity of a sound wave in air if the temperature of the air increases

Determine the [oh-] concentration of a 0.741 m koh solution at 25°c.

In the lab, students decomposed a sample of calcium carbonate by heating it over a Bunsen burner and collected carbon dioxide according to the following equation: CaCO3 (s) CaO (s) CO2 (g) (a) How many mL of carbon dioxide gas were generated by the

J. J. Thomson A) Electrons are in orbital levels. John Dalton B) Atoms are the smallest unit of an element. Ernest Rutherford C) Electrons are scattered within the atom. Niels Bohr D) Protons are at the center of an atom.

Which answer best describes an alloy