A student is analyzing an unknown substance. The substance is solid at room temperature, but when heated only slightly, it melts. It boils when placed over a flame for more than a few seconds. The student dissolves the substance in water and finds the solution does not conduct electricity. Based on the experimental evidence, how should the student categorize the molecules that make up this substance? A:ionic compounds

B:transition metals

C:radioactive

D:covalent compounds

The big bang nucleosynthesis theory states that elements were produced in the first few minutes of the big bang while elements have their origins in the interiors of stars, forming much later in the history of the universe.

Amines are good nucleophiles, even though they are neutral molecules. how would the rate of an sn2 reaction between an amine and an alkyl halide be affected if the polarity of the solvent is increased? amines are good nucleophiles, even though they are neutral molecules. how would the rate of an reaction between an amine and an alkyl halide be affected if the polarity of the solvent is increased? because both reactants in the rate-limiting step are neutral, the reaction will be faster if the polarity of the solvent is increased. because both reactants in the rate-limiting step are neutral, the reaction will be slower if the polarity of the solvent is increased. because both reactants in the rate-limiting step are neutral, the reaction will occur at the same rate if the polarity of the solvent is increased. request answer

What are the similarities between compounds and mixtures?