How many valence electrons does Iron (Fe) have? How do you know?

Water can be a solid liquid, or gas in Earth's water cycle. Identify two processes in the water cycle where water changes from one state to another state and then back to the original state.

Describe a solution and tell if the parts are mixed chemically or physically.

For a reaction, a plot of ln K versus inverse temperature is found to be linear and fits the following equation: y = - 1,498x + 7.14. What is the value of ΔH? Give your answer with units of kJ/molK; however, you should not type in the units

How would you separate a mixture of water, sand, salt and iron filings into its four component parts

Which of the answer choices best describes elements? homogeneous mixtures, always solid, pure substances, very dense.

How many grams of compound are present in 4.18 grams of K2HPO4

What does the first law of thermodynamics say? A. Energy cannot be stored in any form. B. Energy cannot be created or destroyed. C. Energy cannot move within a system. D. Energy cannot enter or leave a system,

How did the experiement with the iron filings and sulfur compare with the experiment in which copper sulfate pentahydrate was heated? Both resulted in gas formation. Both resulted in color change. Both involved chemical change.

Sodium chloride was dissolved in water to produce a 1.5M solution. Explain what this concentration tells us about the NaCl solution. How might a chemist use this ratio?

A gas is contained in a 5.0-liter container at a pressure of 100 kPa. What size container would be required to contain the gas at a pressure of 50 kPa, assuming the temperature remains constant?