A compound is a pure substance formed by the chemical combination of two or more different elements.
A compound may be splitted into simpler substances by chemical reactions, and has different properties to those of the elements that form it.
The composition of a compound is fixed: every piece of a compound has the same kind of atoms, bonded in the same way and proportion.
Some examples of compounds are H₂O, NaCl, H₂O₂, CH₃COOH. As you see, they have a chemical formula which states the kind and number of the atoms that form them.
They are different to mixtures, which are formed by two or more compounds, in a variable proportion, and can be separated by physical media. Some examples of mixtures are the solutions (e.g. NaCl dissolved in H₂O), and some solid mixtures (e.g. a mixture of marbles and sand).
My sample would be 4000 years old because on my graph, I had about 9 Virtualium left at trial 4 so I am guessing that it would be 4000 years old.
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Answer: The possible molecular formula will be 
Explanation:
Mass of C= 27.3 g
Mass of O = 72.7 g
Step 1 : convert given masses into moles.
Moles of C =
Moles of O =
Step 2 : For the mole ratio, divide each value of moles by the smallest number of moles calculated.
For C = 
For O =
The ratio of C : O = 1: 2
Hence the empirical formula is
The possible molecular formula will be=
Answer:
Copper is a metal made up of copper atoms closely packed together. As a result, the electrons can move freely through the metal. For this reason, they are known as free electrons. They are also known as conduction electrons because they help copper be a good conductor of heat and electricity.
Explanation:
