We are given with the following pairs:
<span>carbon and oxygen
hydrogen and helium
gold and silver
and we are asked if there is a pair that will produce the same spectrum. The answer is
</span>No two elements produce the same spectrum.This is because a light spectrum is unique to each element.
The method that can be used to separate the mixture is chromatography.
<h3>
What is chromatography?</h3>
"Chromatography" is obtained form a Greek word which literarily means, color writing. It is a method of separation which is common in separating a mixture of pigments.
To obtain the colors used, two solvents are mixed and the sample ink is dissolved in the solvents then spotted on a thin layer and put into a TLC chamber then the chromatogram is allowed to develop.
The various components of the pigment will appear on the chromatogram and can be identified using spectrophotometry. The Rf values of each component can also be used to identify it.'
Learn more about chromatography: brainly.com/question/26491567
Melting can be best described as a process in which molecules gain enough kinetic energy to be able to pass to each other.
Answer: 
Explanation:
A single displacement reaction is one in which a more reactive element displaces a less reactive element from its salt solution. Thus one element should be different from another element.

Synthesis reaction is defined as the reaction where substances combine in their elemental state to form a single compound.
Decomposition reaction is defined as the reaction where a single substance breaks down into two or more simpler substances.

Combustion is a type of chemical reaction in which hydrocarbons burn in the presence of oxygen to form carbon dioxide and water along with heat.

44g of CO2 can produce by the reaction of carbon with oxygen