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Chem question of death (1 Viewer)

Real Madrid

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Stuck on this one for an hour

One method of extracting nickel from concentrated ores is to mix finely divided ore with carbon monoxide. Nickel reacts to form gaseous nickel carbonyl. When excess nicket was reacted with 500 ml CO, 125 ml nickel carbonyl was formed at the same temperature and pressure. Assuming all the CO reacted, what is ther formula of nickel carbonyl? Explain how you deduced thi.
 

shaon0

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Real Madrid said:
Stuck on this one for an hour

One method of extracting nickel from concentrated ores is to mix finely divided ore with carbon monoxide. Nickel reacts to form gaseous nickel carbonyl. When excess nicket was reacted with 500 ml CO, 125 ml nickel carbonyl was formed at the same temperature and pressure. Assuming all the CO reacted, what is ther formula of nickel carbonyl? Explain how you deduced thi.
Use stoichiometry but they should give mass, concentration, volume or moles of Nickel or other constituents of the 'equation'. what type of Nickel was it? Nickel (II) or Nickel(III)...
Weird question
 
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bored of sc

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Real Madrid said:
Stuck on this one for an hour

One method of extracting nickel from concentrated ores is to mix finely divided ore with carbon monoxide. Nickel reacts to form gaseous nickel carbonyl. When excess nicket was reacted with 500 ml CO, 125 ml nickel carbonyl was formed at the same temperature and pressure. Assuming all the CO reacted, what is ther formula of nickel carbonyl? Explain how you deduced thi.
Ni(CO)4

Equation is as follows:

Ni + xCO --> Ni(CO)y

Since 500mL of CO reacts to form 125mL, Equal volumes of ideal or perfect gases, at the same temperature and pressure, contain the same number of particles, or molecules and The ratio between the combining volumes of gases and their reaction product, if gaseous, can be expressed in small whole numbers. the ratio of CO to NiCO is 4:1 (500mL:125mL) - therefore the simplest ratio of moles of CO to NiCO is 4:1 --> Therefore put a 4 in front of the CO and 1 in front of the NiCO (but as you know you don't write the one due to convention).

Ni + 4CO --> Ni(CO)y

Now balance the equation - 4 C's and 4 O's on the first side means there must be 4 C's and 4 O's on the second side... therefore y = 4

Thus giving: Ni + 4CO --> Ni(CO)4

Note: CO in the products is in brackets due the ratio of moles of CO to NiCO --> you can only put a 1 in front of the NiCO to stay within the ratio established from the volumes of gases. Therefore the only way to balance is to put brackets around the CO to give each C and O a 4.

P.S I cheated. I used wikipedia to get the fomula :)() - but I deduced the working out myself.
 
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st1m

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lol i had that question, worksheet 14? yeah i answered it.

In other words the ratios are 4:1, therefore there are 4 CO to 1 carbonyl.

Which means to balance out, put (CO)4
 

shaon0

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what if the valencies of Nickel are different example 3. and you didn't know the formula for NiCO
 

Continuum

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shaon0 said:
what if the valencies of Nickel are different example 3. and you didn't know the formula for NiCO
I had to do exactly the same question for homework. I think it's impossible to answer it without more information for the reason stated above. If anybody can answer it without making ANY assumptions, I'll shoot myself since I'm pretty sure about this. :uhhuh:
 

shaon0

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Continuum said:
I had to do exactly the same question for homework. I think it's impossible to answer it without more information for the reason stated above. If anybody can answer it without making ANY assumptions, I'll shoot myself since I'm pretty sure about this. :uhhuh:
yes the question requires more information to be answered
 

Aerath

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Look at the answers? *nods*
Always worked for me.
 

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