How is a pure substance different from a mixture?

A

Pure substances cannot be separated by physical means

B

Mixtures cannot be separated

C

A pure substance is heterogeneous

D

A mixture is made of one substance

Adrienne noticed a puddle in her driveway after a rain storm before the sun came out. Later that afternoon, she noticed the puddle was much smaller. What made the puddle become smaller?

A 1.0l buffer solution contains 0.100 mol of hc2h3o2 and 0.100 mol of nac2h3o2. the value of ka for hc2h3o2 is 1.8*10-5. part a calculate the ph of the solution upon the addition of 0.015 mol of naoh to the original buffer.

Nitric acid in acid rain forms when gaseous nitrogen dioxide pollutant reacts with gaseous oxygen and liquid water to form aqueous nitric acid. Write a balanced chemical equation for this reaction. Express your answer as a chemical equation.

What is absolute dating?

Out of these: which is an acid, base or neutral 1. NaCl 2. Na2SO4 3. AlCl3 4. Li3PO4 5. ZnBr2

The reaction below has an equilibrium constant kp=2.2*106 at 298 k. 2cof2 (g) ⇌co2 (g) + cf4 (g) calculate kp for the reaction below. cof2 (g) ⇌12co2 (g) + 12cf4 (g)

The electrical conductivities of the following 0.100 M solutions were measured in an apparatus that contained a light bulb as the indicator of conductivity. Rank the solutions in order of decreasing intensity (brightest to dimmest) of the light bulb.

What is the name of a list of elements arranged according to the ease with which they undergo certain chemical reactions?

Why is it harder for the earth to recover from some natural disasters now? A) Human influence may compound the damage. B) The natural disasters have gotten worse. C) This statement is not true.

Heat is most closely related to ___ energy. A. Nuclear B. Electrical C. Thermal