(b) Give the reason why water is a better fuel than producer gas.
(a) Components
(i) Producer gas: carbon(II) oxide (CO) and nitrogen (N2), together with a small amount of carbon(IV) oxide (CO2). It is made by passing air over red-hot coke.
(ii) Water gas: carbon(II) oxide (CO) and hydrogen (H2). It is made by passing steam over red-hot coke: \[C_{(s)} + H_2O_{(g)} \rightarrow CO_{(g)} + H_{2(g)}\]
(b) Why water gas is the better fuel
Water gas is a better fuel than producer gas because both of its components, carbon(II) oxide and hydrogen, are combustible and release heat when burnt. Producer gas, on the other hand, contains a large proportion (about half) of nitrogen, which is chemically inert and does not burn. This non-combustible nitrogen dilutes the fuel and carries away heat, so producer gas has a much lower calorific (heat) value than water gas.
(i) Producer gas: carbon(II) oxide (CO) and nitrogen (N2), together with a small amount of carbon(IV) oxide (CO2). It is made by passing air over red-hot coke.
(ii) Water gas: carbon(II) oxide (CO) and hydrogen (H2). It is made by passing steam over red-hot coke: \[C_{(s)} + H_2O_{(g)} \rightarrow CO_{(g)} + H_{2(g)}\]
(b) Why water gas is the better fuel
Water gas is a better fuel than producer gas because both of its components, carbon(II) oxide and hydrogen, are combustible and release heat when burnt. Producer gas, on the other hand, contains a large proportion (about half) of nitrogen, which is chemically inert and does not burn. This non-combustible nitrogen dilutes the fuel and carries away heat, so producer gas has a much lower calorific (heat) value than water gas.