What volume of 0.500 mol/l hydrochloric acid, hci (aq) is required to react completely with 1.00 g of aluminum hydroxide, ai(oh)3 (s)?

Molar mass CaCO3 is 100g/mol Your 10g is therefore 0.1mol  

0.1mol CaCO3 will react with 0.2mol HCl  

Your acid is 0.5mol per 1000ml  

0.2mol = 0.2/0.5/1000 = 400ml

the product of the pressure and volume is also constant

answer:

the answer is 6 valence electrons.

explanation:

valence is the # of electrons on the outer most shell of an atom.

oxygen has 6.

although, the valency of oxygen is 2, because it only needs to make 2 covalent bonds, or gain 2 electrons, to achieve the stable octet configuration of a noble gas.

that's it!

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~ trueboss72