Combustion
The chemical change that occurs is that the atoms move around with the chemical change. Whereas the physical change will keep the candle moving in a normal way.
Oxidation.
The Hydrocarbon composition of the wax varies and is a mix of C20 to C40 so an exact equation can not be given. However, it is a standard combustion reaction. i.e. CxHy + (x + y/4) O2 ---> (y/2) H2O + (x) CO2
The little numbers (subscripts) are coefficients. A chemistry reaction is like a math equation: whatever is on one side has to equal whatever is on the opposite side. The coefficients take care of that. They look confusing in the reaction shown because they are letters, but if you stick numbers in there it would be much easier to understand. Let us use an example of C25 which would be C25H52.
C25H52 + 38 O2 ------- 25CO2 + 26 H2O + energy (heat and light)
When you burn a candle, you are performing simple combustion reactions of this type. The oxygen comes from the air and the heat initially comes from an outside source such as a match. When this combustion reaction happens, it makes water and carbon dioxide as shown as well as heat and light energy. The coefficients tell us how much of each component is used and produced.
The wick in a candle is also mainly hydrocarbon with oxygen also present and this also burns though at a much slower rate. When you light the wick, you provide a heat source and oxygen from the air. The smoke formed contains carbon dioxide and water and also some soot from inneficient combustion.
Some wax burns, and as it does so, chemical changes occurs. Wax converts to CO2, CO, and H2O. That is an exothermic reaction The rest of the wax melts with the increased temperature. That is the physical change.
Yes. While act of melting wax is a physical change, because you can remould it, the wax is actually what is primarily burned as fuel. You cannot unburn the wick nor the consumed wax. Remember, if it can be redone, it is probably physical and vice versa.The wick of a candle is used to light it and is used as a medium for burning the wax. As the wax is heated, it is soaked into the burning wick. As the fire burns the wax on the wick, more melted wax is absorbed into by the wick. As the wax burns down, so does the wick.
When a candle is burnt a physical AND chemical change takes place. Its a physical change when the wax is being melted because the chemical structure has not change, meaning it cannot be a chemical change. Its also a chemical change because you are burning the string. When you burn something the chemical structure DOES change, meaning it is a chemical change.
Physical changes are like cutting paper. The mass does not change. Chemical changes do not change total mass either. If you put a candle in a sealed container so that you may measure the total mass of the candle and the air before burning, then light the candle electrically but keep everything sealed, the total mass after burning will still be the same. But if you measure only the candle, then its mass has changed. So the mass of one single 'ingredient' will change during a chemical change.
In a traditional candle, the part that burns is the wick. The wick is typically a braided or twisted cord made from natural fibers, such as cotton or hemp, or sometimes from a blend of natural and synthetic materials. If you happen to have time, Please check Ohcans candle. We have more details about candle on our blogpost.
it is a chemical change
Yes. That is a chemical change.
That is correct, a candle (or the material of which it is composed, which is usually paraffin) undergoes a chemical change when it burns.
Some wax burns, and as it does so, chemical changes occurs. Wax converts to CO2, CO, and H2O. That is an exothermic reaction The rest of the wax melts with the increased temperature. That is the physical change.
Yes, soot formation when a candle burns is considered a chemical change. This is because the wax molecules in the candle undergo a chemical reaction with oxygen in the air, resulting in the formation of new substances like carbon dioxide, water vapor, and soot particles.
Burning a candle is a chemical change because the wax undergoes a chemical reaction with oxygen in the air to form new substances like carbon dioxide and water. This process results in the candle getting shorter as it burns.
This is because a candle will change its whole form and stay that way, which is a physical outer change. And a candle wick only burns, it doesn't change it's appearance.
The rate at which a candle burns can vary, but on average, a candle burns at a rate of about 10 millimeters per minute. This rate can change depending on factors such as the size of the candle, its composition, and environmental conditions.
chemical change occurs first. because first oxygen help in burning and form carbon-di-oxide which is a chemical change
As a candle burns, the candle becomes smaller as the wax melts.
There are multiple physical changes and chemical changes that occur when a candle burns. One physical change is that the candle melts back into liquid wax. One chemical change is flame burning on the wick.
Melting is the physical change.