Which best compares and contrasts how John Newlands and Dmitri Mendeleev organized elements?
O Both Newlands and Mendeleev arranged elements according to their chemical properties, but only Newlands used atomic
mass as well.
O Both Newlands and Mendeleev arranged elements according to their atomic masses, but only Mendeleev used chemical
properties as well
O Both Newlands and Mendeleev organized elements into groups, but only Newlands used a table with rows and columns
O Both Newlands and Mendeleev organized elements into a table with rows and columns, but only Mendeleev named
different groups of elements.

in theory, limestone is composed principally of the compound calcium carbonate - caco3, but in reality this compound is deposited in conditions involving a number of other compounds as impurities so it ends up being a mixture of many compounds.

hope this : -)

tony (lordcaos066)

answer:

the reaction is type of combination reaction.

explanation:

on the product side, there are 2 molecules of bonded to fe   which means one atom of fe are combined two molecules of . so, balanced chemical equation becomes :

this reaction follows the reaction type of combination reaction. a combination reaction is defined as chemical reaction in which reactants combines together to form a single product.

im pretty sure its b

the ratio of the conjugate base to the acid required to attain the desired ph.