What distinguishes a substance from a mixture?

A chemistry student needs 40.0 mL of pentane for an experiment. By consulting the CRC Handbook of Chemistry and Physics, the student discovers that the density of pentane is 0.626 g cm^3. Calculate the mass of pentane the student should weigh out.

What is the chemical property of soda ash

A gene or trait that appears or expresses itself over a recessive trait is called an?

A syringe contains 0.65 moles of he gas that occupy 750.0 ml. what volume (in l) of gas will the syringe hold if 0.35 moles of ne is added? a syringe contains 0.65 moles of he gas that occupy 750.0 ml.

Be sure to answer all parts. how would you prepare benzylamine (c6h5ch2nh2) from c6h5cooh? more than one step is required. qsleft1 edit structure ... qsright1 select the correct reagents for each step.

Match the factors which affect the rate of dissolving/dissociation/diffusion.

How would the equilibrium of an exothermic reaction at 25°c be affected if the temperature of the system were reduced? (hint: apply le chatelier's principle) ?

Which is the most practical argument for the continued funding of space exploration? a) Space exploration will one day show whether life exists on other planets in star systems similar to ours.

33 protons 36 electrons 45 neutrons

The periodic table includes all of the known elements in the world. how are elements arranged on the periodic table?