Fill in the blank.

are pure substances that cannot be broken down into a simpler form.

are units of two or more atoms.

are the smallest possible particles of an element.

are pure substances made of two or more atoms of different elements.

Be sure to answer all parts. A 0.365-mol sample of HX is dissolved in enough H2O to form 835.0 mL of solution. If the pH of the solution is 3.70, what is the Ka of HX? Be sure to report your answer to the correct number of significant figures.

How come water and oil separates?

The concentration of barium ions in any solution can also be determined via gravimetric analysis. An impure sample of barium nitrate with a mass of 1.

During a storm, a tree fell over into a river. What might happen to this tree?

What is a cercaria? *zoology

Two clear solutions are placed in separate beakers. The first solution has a pH of 4, and the pH of the second solution is unknown. If the two solutions are mixed and the resulting pH is 5, the second solution must have

Based on its location on the periodic table, which element (s) have properties similar to N? Choose all that apply. * P C O Bi

What conclusion can be drawn from the statement that an element has low electron affinity, low electronegativity, and a low ionization energy?

A scientist performs an experiment in which a radium-226 (Ra-226) atom decays into radon-222 (Rn-222). The scientist concludes that some energy must have been added to the system to cause this reaction to begin.

Which suitable method can be used to separate a mixture of sand and paraffin