What bonding produces substances that are hard, or difficult to crush?

Calculate the percent composition by mass of each element in al(oh)3. use at least three significant figures.

If 2 molecules of one reactant combine with 3 molecules of another to produce 5 molecules of a product, then what is the representation of the reaction?

[08.05] which answer provides the correct name for name the following hydrocarbon? (2 points) moving left to right: a hydrocarbon chain made of a methyl group (ch subscript three) single bond carbon triple bond carbon single bond ch bonded to a methyl group (ch subscript three) and a chain including a methelyne group (ch subscript two) single bond methyl group (ch subscript three). 4-ethyl-2-pentyne 4-methyl-2-hexyne 2-heptyne 4-methy-hexane