| Author | Message | ||
     Pure Emotion Username: 991160 Registered: 04-2003 |
using C8H18 to respresent petrol, write a balance equation for the complete combustion of petrol. explain why this reaction can produce power. equation: 2 C8H18 + 25 O2 -> 16 CO2 + 18 H2O but how to explain the reason...? | ||
| Pure Emotion Username: 991160 Registered: 04-2003 |
i want to ask a question.. a label of oxidizing agent should be put on a bottle of conc. nitric acid.. i don't understand why there is a need to put on this label. moreover, is there a need that put this label on any kind of oxidizing agent? | ||
| Pure Emotion Username: 991160 Registered: 04-2003 |
2 SO2(g) + O2(g) <=> 2 SO3(g) (-197kJ mol*-1) applying this reaction to the industrial preparation of sulphur trioxide.. in the following case... reactants: excess SO2 + air temperature: 500 pressure: 2atm catalyst: Pt will excess SO2 increase the cost of production? why? | ||
| Pure Emotion Username: 991160 Registered: 04-2003 |
what is "TEL" in the leaded petrol? | ||
| 991073 Username: 991073 Registered: 04-2003 |
what isthe catalyst of contact process, Pt or Vanadium (V) oxide?? | ||
| 991073 Username: 991073 Registered: 04-2003 |
I think there is a label of oxidizing agent put on a bottle of conc. nitric acid as conc. nitric acid is an oxidizing agent ~ | ||
| Pure Emotion Username: 991160 Registered: 04-2003 |
i know there is a label of oxidizing agent put on a bottle of conc. nitric acid... i know it's an oxidizing agent... i want to know what's the use... and how about other oxidizing agent, is there a need to put on the label of oxidizing agent? | ||
| Pure Emotion Username: 991160 Registered: 04-2003 |
i think it's almost vandium (v) oxide... because Pt is expensive... i think it's the answer if i remember it correctly.. | ||
| Chio U Kim Username: cuk Registered: 04-2003 |
An oxidizing agent such as conc. nitric acid can react vigorously with other substances. Some other oxidizing agents can even catch fire(Don't you notice that the 'oxidizing' label looks very similar to the 'flammable' label?) when mixed with suitable chemicals. Therefore, safety labels are needed on bottles containing oxidizing agents. | ||
| Chio U Kim Username: cuk Registered: 04-2003 |
Of course, a warning label is required only for a strong oxidizing agent! | ||
| Chio U Kim Username: cuk Registered: 04-2003 |
1. The combustion of petrol can produce power because it is an exothermic reaction. 2. In Contact process, an excess of SO2 is used to increase the yield of the SO3. 3. TEL is an anti-knocking agent added to petrol to improve its performance. The full name of TEL is TetraEthyl Lead. Since it contains lead, petrol with TEL is called leaded petrol. 4. Both Pt and V2O5 can be used as catalysts in the Contact process. Pt is more efficient as a catalyst than V2O5 but more easily poisoned by impurities. Pt is also more expensive than V2O5. So, V2O5 is more commonly used. | ||
| Pure Emotion Username: 991160 Registered: 04-2003 |
thanks mr chio. but in number2, i want to know why excess SO2 increase the cost of production? | ||
| Chio U Kim Username: cuk Registered: 04-2003 |
An excess of SO2 is used to increase the yield (²£¶q)of the SO3! | ||
| Pure Emotion Username: 991160 Registered: 04-2003 |
The reason why excess SO2 increase the cost of producing SO3 is excess SO2 is used to increase the yield of SO3...? | ||
| 991073 Username: 991073 Registered: 04-2003 |
1) NaCl(s) + H2SO4(aq) ->NaHSO4(aq) + HCl(aq) 3H2SO4(aq) + 2NaBr(s) -> 2NaHSO4(aq) + Br2(g) SO2(g) + 2H2O(l) This two equation in syl or out syl???? 2) Sulphite (SO3 2-) is an oxidizing agent or reducing agent?? | ||
| Chio U Kim Username: cuk Registered: 04-2003 |
The second reaction is not required in the syllabus. Sulphite behaves mainly as a reducing agent. However, the oxidation number of S (+4)in sulphite is in an intermediate oxidation state, therefore, it can undergo both reduction (+4 to 0 or even -2) and oxidation (+4 to +6) and can act as an oxidizing agent as well as a reducing agent. |