Question

A kerosene lamp has a mass of 1.5 kg. You put 0.5 kg of kerosene in the lamp. You burn all thekerosene until the lamp has a mass of 1.5 kg. What is the mass of the gases that are given off?Explain.

Short answer

The mass of the gases that are given off is 0.5 kg.

Step-by-step solution

Formation of reaction using given data

It is given that the mass of the kerosene lamp is 1.5 kg, and 0.5 kg of kerosene is put in the lamp. The kerosene is burnt until complete evaporation. The equation can be denoted as,

$$\begin{gathered} \text{1.5kg\hspace{0.05em}+\hspace{0.05em}0.5kg\hspace{0.05em}-x\hspace{0.05em}=\hspace{0.05em}1.5kg} \\ \text{x\hspace{0.05em}=\hspace{0.05em}0.5kg} \end{gathered}$$

Using the law of conservation of mass

Mass can neither be created nor destroyed according to the law of conservation of mass. However, it can be changed from one state to another. All the kerosene is burnt, and there is a conversion from liquid to a gaseous state. Therefore, the mass of the gases that are given off is 0.5 kg.