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Help me ,Chemistry questions !?
in Ca(OH)2 what does the two stand for? Is it the charge or does it show the number of molecules? Also how do you write and balance this equation?
phosphoric acid and calcium hydroxide react to form calcium phosphate and water.
3 Answers
- 1 decade agoFavorite Answer
the brackets mean that you multiply everything in them by 2, so Ca stays the same but O is now O2 and H is now H2, this can not be balanced until i know what the reactants and products are, there should be an arrow showing another side of the equation
sorry didnt see the other part of the question...what is the formula for phosphoric acid? then i can answer it lol
Source(s): in chemistry grade 10 right now - jencsiLv 61 decade ago
I believe the 2 refers to the number of OH so there are 2 OH's. To balance it put a 2 infront of the Ca. written out it would be calcium hydroxide.
- caroline mLv 61 decade ago
the 2 stands for both the number of OH- ions present in the compound and the charge on the Ca+2 ion. when writing ionic compounds, one needs to know the charges on each ion.
Ca+2 + OH- to write this, lose the signs (+ and -) on the numbers and cross the numbers over to the other ion. Ca+2OH- yields Ca(OH)2. if you write this as CaOH2, this is incorrect since this tells us that you only have 1 oxygen and 2 hydrogen atoms. the correct formula of Ca(OH)2 tells us that there are 2 OH- ions.
2H3PO4 + 3Ca(OH)2 --> 6H2O + Ca3(PO4)2
