Why is elemental zinc considered a pure substance?

Which characteristic gives the most information about what kind of element an atom is? A. The atomic number B. The atomic mass C. The number of electrons D. The number of neutrons

A rock at the top of a 30 meter cliff has a mass of 25 kg. Calculate the rock's gravitational potential energy when dropped off the cliff. Assuming that energy is conserved and there is no air friction and gravity is 9.8 m/sec.

What are ten facts about the Precambrian era?

Explain the hydrogenation of oil

What is HC2H3O2 in science

A small 15 kilogram canoe is floating downriver at a speed of 4 m/s. What is the canoe's kinetic energy?

Liquid water is heated until it boils and becomes water gas. Which statement is true about the water?

You are conducting an experiment on plant growth. You take a plant fresh from the soil that weighs 5 kilograms (kg). Then you dry the plant overnight and determine the dry weight to be 1 kg.

What is the ratio of Fe+3 ions to O2 - ions in a neutral compound? a. 1:2 b. 2:1 c. 2:3 d. 3:2

What is the specific heat capacity of a 17.5g sample of an unknown metal that releases 6700J of heat when it cools from 90 to 25 degrees C?