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    silicon carbide, used for cutting and grinding tools, is made by the reaction of silicon dioxide with carbon graphite. SIO2+3C=SIC+"CO if 100g of SIO2 and 100g of C are reacted as far as possible, which one of the following statements will be correct? a) 111g of SIO2 will be left over
    b) 44g of SIO2 will be left over
    c) 82g of C will be left over
    d) 40g of C will be left over
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    (Original post by jackiemcnair)
    silicon carbide, used for cutting and grinding tools, is made by the reaction of silicon dioxide with carbon graphite. SIO2+3C=SIC+"CO if 100g of SIO2 and 100g of C are reacted as far as possible, which one of the following statements will be correct? a) 111g of SIO2 will be left over
    b) 44g of SIO2 will be left over
    c) 82g of C will be left over
    d) 40g of C will be left over
    Hey,
    I would say the answer is D.
    The reaction is SiO2 + 3C --> SiC + 2CO
    SiO2: 60.1
    100/60.1=1.66mol
    C:12
    100/12=8.33mol

    You can see that the graphite is excess as only 4.99mol of graphite was required for a complete reaction.

    Substrat the moles, 8.33-4.99=3.34mol
    12x3.34=40.1g
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    (Original post by jackiemcnair)
    silicon carbide, used for cutting and grinding tools, is made by the reaction of silicon dioxide with carbon graphite. SIO2+3C=SIC+"CO if 100g of SIO2 and 100g of C are reacted as far as possible, which one of the following statements will be correct? a) 111g of SIO2 will be left over
    b) 44g of SIO2 will be left over
    c) 82g of C will be left over
    d) 40g of C will be left over
    If you have any more questions about higher chemistry, you can post them here on the CfE Higher Chemistry thread:http://www.thestudentroom.co.uk/show....php?t=4282042
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    (Original post by mat7276)
    Hey,
    I would say the answer is D.
    The reaction is SiO2 + 3C --> SiC + 2CO
    SiO2: 60.1
    100/60.1=1.66mol
    C:12
    100/12=8.33mol

    You can see that the graphite is excess as only 4.99mol of graphite was required for a complete reaction.

    Substrat the moles, 8.33-4.99=3.34mol
    12x3.34=40.1g
    thank you
 
 
 
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