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    how many grams of calcium phosphate can be produced from 5.00 grams of calcium hydroxide according to the following equation?

    Ca(OH) + H3PO4 > H2O + Ca3(PO4)2
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    (Original post by J_riley18)
    how many grams of calcium phosphate can be produced from 5.00 grams of calcium hydroxide according to the following equation?

    Ca(OH) + H3PO4 > H2O + Ca3(PO4)2
    What's the stoichiometry - the ratio of moles which react with one another.
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    (Original post by Reality Check)
    What's the stoichiometry - the ratio of moles which react with one another.
    yes this Intro of chemistry
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    ^^^ what Plantagenet said
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    1. work out the moles of calcium hydroxide= mass/molecular mass
    2. ratio of hydroxide to calcium phosphate 1:1, so moles of phosphate is same as ans 1.
    3. rearrange the equation in (1.) moles x molecular mass= mass of phosphate in grams.
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    (Original post by Plantagenet Crown)
    Divide 5 g by Ca(OH)2's molar mass to work out the moles of Ca(OH)2. As the stoichiometry of the reaction shows that 1 mol of Ca(OH)2 produces 1 mol of Ca3(PO4)2, you multiply the number of mols you worked out in the first part by Ca3(PO4)2's molar mass to get the answer.
    OP has not provided a balanced equation, or even one with the correct forulae.
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    Come on folks balance the equation first.
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    (Original post by TeachChemistry)
    OP has not provided a balanced equation, or even one with the correct forulae.
    Yeah, I just saw another thread he made and now I think he/she is a troll.
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    I am not a troll
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    (Original post by TeachChemistry)
    OP has not provided a balanced equation, or even one with the correct forulae.
    could you show me how to solve this problem
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    (Original post by J_riley18)
    could you show me how to solve this problem
    Tell me how old you are so I know your level of study. I will then talk you through it and hopefully get you to understand it.
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    (Original post by TeachChemistry)
    Tell me how old you are so I know your level of study. I will then talk you through it and hopefully get you to understand it.
    I am 19 I'm a freshman in college this is the introduction of chemistry class
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    (Original post by J_riley18)
    I am 19 I'm a freshman in college this is the introduction of chemistry class
    Can you correct the formula of calcium hydroxide in your OP and balance the equation? In the UK a 15 or 16 year old should be able to do this so I am surprised if you can not.
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    (Original post by TeachChemistry)
    Can you correct the formula of calcium hydroxide in your OP and balance the equation? In the UK a 15 or 16 year old should be able to do this so I am surprised if you can not.
    Is this correct 3Ca(OH)2+ 2H3PO4= H20+Ca3(PO4)2 +6H20 I haven't had chemistry since 9 grade I forgot a lot
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    (Original post by J_riley18)
    Is this correct 3Ca(OH)2+ 2H3PO4= H20+Ca3(PO4)2 +6H20 I haven't had chemistry since 9 grade I forgot a lot
    You've made one small error but are otherwise correct. Look again and try to spot it.
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    (Original post by TeachChemistry)
    You've made one small error but are otherwise correct. Look again and try to spot it.
    I had two H20 in the equation and I needed one. I see it now but does that answer my original question above? Still need help
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    (Original post by J_riley18)
    I had two H20 in the equation and I needed one. I see it now but does that answer my original question above? Still need help
    According to your now balanced equation, how many moles of calcium hydroxide reactant are needed to make one mole of calcium phosphate? And do you know the equation linking moles, mass and relative formula mass?
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    (Original post by TeachChemistry)
    According to your now balanced equation, how many moles of calcium hydroxide reactant are needed to make one mole of calcium phosphate? And do you know the equation linking moles, mass and relative formula mass?
    Now I'm getting confuse it the molar mass of calcium phosphate 87 I don't know what to do next
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    (Original post by J_riley18)
    Now I'm getting confuse it the molar mass of calcium phosphate 87 I don't know what to do next
    Firstly work out the relative formula mass of calcium hydroxide. This contains one calcium, two oxygens and two hydrogens. Work this out and make sure you understand where the znumbers came from. Post your answer to this bit.
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    (Original post by TeachChemistry)
    Firstly work out the relative formula mass of calcium hydroxide. This contains one calcium, two oxygens and two hydrogens. Work this out and make sure you understand where the znumbers came from. Post your answer to this bit.
    Okay is 74.093 right?
 
 
 
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