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Moles (1 Viewer)

kittyful

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I got some mole questions i got stuck with any help would be appreciated haha :D

1. What volume of oxygen is required for the complete combustion of 125mL of butene gas (C4H8) and what volume of carbon dioxide is formed? (All volumes are measured at the same temperature and pressure)

Answer is 750ml O2, 500ml CO2 -


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

Answer is Ni(CO04

3. Butane is used in fuel camping stoves. The equation for the complete combustion of butane is:
2C4H10 + 13O2 = 8CO2 +10H20

100 ml of butane is burnt in an excess of oxygen. Calculate:
a) the volume of oxygen comsumed
b) the volume of carbon dioxide produced

(all volumes measured at same temperature and pressure)

Anwser a) 650ml, b) 400ml

Please provide working out for solutions :D any help would be appreciated :D
 
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1. C4H8 + 6O2 --> 4CO2 + 4H2O

6 moles of oxygen is reacted for every mole of butene. 6 * 125 mL = 750 mL, .: 750 mL of oxygen is reacted.

4 moles of carbon dioxide is produced for every mole of butene. 4 * 125 mL = 500 mL, .: 500 mL of carbon dioxide is produced.
 
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2. A mole of any gas has the same volume when temperature and pressure is constant. The volume of nickel carbonyl is 1/4 of the carbon monoxide, .: each nickel atom must have reacted with 4 carbon monoxide molecules, .: Ni(CO)4.
 
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3. a) 13 moles of oxygen is reacted for every 2 moles of butane. 6.5 moles of oxygen is reacted for every mole of butane. 6.5 * 100 mL = 650 mL, .: 650 mL of oxygen is reacted.

b) 8 moles of carbon dioxide is produced for every 2 moles of butane. 4 moles of carbon dioxide is produced for every moles butane. 4 * 100 mL = 400 mL, .: 400 mL of carbon dioxide is produced.
 

kittyful

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Thanks for your help :D ... i really appreciated it :D
 

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