Answer: pure substances.
Explanation:
The given substances are:
All what surrounds us, which has mass and occupies spaces, is matter. There are two kind of matter: pure substances and mixtures.
Pure substances have a uniform and constant composition. On the other hand, mixtures are combinations of two or more pure substances in any arbitratry ratio.
Pure substances may be elements or compounds. The elements are the substances conmposed by one only kind of atom. In the list of substances given, Li and O₂ are elements: all the atoms in Li are lithium, and all the atoms in O₂ are oxygen atoms.
Compounds are the chemical combination of two or more different kind of atoms. In the given list H₂O₂ and NaCl are compounds. As you see, H₂O₂ contains atoms of hydrogen and oxygen, chemically bonded, in a fixed ratio (2 atoms of hydrogen by 2 atoms of oxygen). And NaCl has atoms of Na (sodium) and Cl (chlorine), chemicaly bonded, in a fixed ratio (1:1).
There are only 118 known elements and you can find them in any modern periodic table. Therer are virtually infinitely many compounds since many different combinations of the elements can be attained.
Elements and compounds have in common that they are classified as pure substances.
Causes carbon to move from one reservoir to another
1.54×10 −10
one and fifty four-hundreths times ten to the power of negitiive 10
The general formula for alkenes is CnH2n, the formula with hydrogen count double the carbon count should be the correct formula for alkene and that is d. C3H6.
What are alkenes?
Alkenes, commonly known as olefins, are organic unsaturated hydrocarbons that have one or more carbon-carbon double bonds in their chemical structure and are composed of carbon and hydrogen atoms.
Alkenes are unsaturated hydrocarbons with a double bond between the carbon atoms. Carbon atoms are connected by at least one double bond. The general formula for alkenes is C n H 2n. Olefin is frequently substituted with alkenes. The word "olefin" comes from the Greek phrase "olefin gas," which denotes the production of oil.
<u>Since, their general formula is CnH2n, the formula with hydrogen count double the carbon count should be the correct formula for alkene and that is d. C3H6.</u>
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