Why does the bottom of the inner blue cone of a bunsen burner have such a low temperature compared to the rest of the flames? Is this due to the outside flames being in contact with oxygen, while the inner flame receives a low amount of oxygen?
The inner cone has no oxygen(it's just pure gas).; therefore, there is no combustion and no heat generated. In fact, the next time you have a chance, take a match and thrust it quickly so that the head of the match is WITHIN the cone that is below the tip and the burner. The match will not ignite. The match STICK between your hand and the match head will catch on fire and eventually that will lead to the match igniting but the heat comes from the match stick and the outer edges of the cone and not from the inner part of the cone.
The temperature variation in the different regions of a Bunsen burner flame is indeed influenced by the amount of oxygen present. To understand this, we need to examine the structure of the flame.
A Bunsen burner flame consists of multiple zones with varying temperatures and chemical reactions. At the base of the flame, you have the inner blue cone, also known as the reducing zone. The outer part of the flame is the oxidizing zone. Let's break it down:
1. The inner blue cone: This is the point where the fuel gas (such as methane) combines with a limited amount of oxygen. In this region, the oxygen present is insufficient for complete combustion, resulting in a fuel-rich environment. The fuel and the oxygen molecules react partially, producing a luminous blue flame. Due to incomplete combustion, the temperature in this region is relatively low.
2. The outer oxidizing zone: Surrounding the inner blue cone, there is a region with sufficient oxygen. Here, the fuel gas mixes with an adequate amount of oxygen, leading to complete combustion. This combustion process generates a high-temperature, non-luminous outer flame. The temperature in this zone is significantly higher compared to the inner cone.
So, the reason for the lower temperature in the bottom of the inner blue cone is the limited amount of oxygen available for combustion. The outer flame zone, in contact with oxygen, is able to undergo complete combustion, resulting in higher temperatures.
The reason why the bottom of the inner blue cone of a Bunsen burner flame has a lower temperature compared to the rest of the flames is not primarily due to the amount of oxygen it receives. Instead, it is related to the combustion process occurring within the flame.
The Bunsen burner flame consists of different regions with varying temperature and oxygen availability. At the outermost part of the flame, where the flame is yellow, a process called incomplete combustion occurs due to a lack of sufficient oxygen. This region is relatively cooler.
As you move towards the inner blue cone of the flame, there is enough oxygen available for complete combustion to take place. In this region, the fuel, usually methane or natural gas, reacts fully with oxygen, resulting in a more intense and hotter blue flame.
However, at the very bottom of the inner blue cone, where primary combustion occurs, the available oxygen is limited due to the surrounding gases and combustion products. This limitation affects the combustion process, leading to a decrease in temperature.
In summary, the lower temperature at the bottom of the inner blue cone of a Bunsen burner flame is primarily due to the limited oxygen availability in that region, which affects the combustion process.