I am unable to read your profile, so I cannot access the information you are speaking of. If you are looking for identification of an unknown substance, I recommend taking it to your local police department so it can be identified and then disposed of if it is dangerous.
You may be able to get a free lab type identification on an unknown substance by contacting your local law enforcement agency or a university with a forensic science program. They may have the resources to analyze the substance for you. Additionally, you could reach out to non-profit organizations or government agencies that offer free testing services for certain substances.
Density is useful for identifying an unknown material because it is a physical constant. A physical constant is a unique characteristic of the material in question. This constant never change or vary with the shape or amount of the material/substance.
cellulose and starch
Cellulose and starch
If you mean what substances are present in paper, then it is principally cellulose. If you are asking about substance A in a question paper, it's a way of referring to an unknown substance so it can ask you questions based on the information given about it. For instance, if it says 'substance A turns damp red litmus blue' then you know that substance A is an acid.
An Element ... A substance that cannot be broken down into simpler substances by chemical means.
Tomb of the Unknown Soldier Guard Identification Badge was created on 1958-02-07.
what is the unknown substance of a glass of milk for a week
Density is useful for identifying an unknown material because it is a physical constant. A physical constant is a unique characteristic of the material in question. This constant never change or vary with the shape or amount of the material/substance.
Cellulose and starch
cellulose and starch
Cellulose and starch
Knowing the melting point of a substance provides information to determine what the substance is if its unknown. If you are making a substance, checking the melting point will let you know if you have made what you set out to make, (because impurities can mess up the melting point)
unknown
You think probable to an atom.
Natalie Portman does not maintain a Funny or Die profile, but that does not mean that someone hasn't done a profile with her name attached to it, and completely unknown to her.
Knowing the solubility of an unknown substance in water can help you calculate its molarity. It is however important to get its weight first.
Density information for a substance is useful because it is always the same regardless of the amount of substance there is. Take water for example. The density of water is same regardless if you have ten gallons of it or tablespoon of it. (1 gram/milliliter at STP). Since the density of a substance is always the same this property can exploited to determine the identity of unknown substances.