Write 20 amazing facts related to compounds and elements
Answers
Explanation:
Compound, in chemistry, a substance composed of atoms of two or more elements in chemical combination, occurring in a fixed, definite proportion and arranged in a fixed, definite structure. A compound is often represented by its chemical formula. The formula for water is H2O, and for sodium chloride, NaCl. The formula weight of a compound can be determined from its formula. The molecular weight of a molecular compound can be determined from its molecular formula. Two or more distinct compounds that have the same molecular formula but different properties are called isomers.
Formation and Decomposition of Compounds
Compounds are formed from simpler substances by chemical reaction. Some compounds can be formed directly from their constituent elements, e.g., water from hydrogen and oxygen: 2H2 + O2 → 2H2O. Other compounds are formed by reaction of an element with another compound; e.g., sodium hydroxide (NaOH) is formed (and hydrogen gas released) by the reaction of sodium metal with water: 2Na + 2H2O → 2NaOH + H2↑. Compounds are also made by reaction of other compounds; e.g., sodium hydroxide reacts with hydrogen chloride (HCl) to form sodium chloride and water: HCl + NaOH → NaCl + H2O. Complex molecules such as proteins are formed by a series of reactions involving elements and simple compounds.
An element is defined by the IUPAC as a pure chemical substance composed of atoms with the same number of protons in the atomic nucleus. All atoms of an element have the same number of protons.
Atoms of elements can have different number of electrons and neutrons.
A variant of an element with different number of neutrons is known as its Isotope
Different physical form of an element is known as its (e.g. graphite and diamond) Allotrope
Element most abundant in the Universe Hydrogen
Element most abundant in the human body Oxygen
Element which forms more than 10 million compounds Carbon
Element with the lowest melting and boiling point Helium
Element with the highest melting point Carbon
Element with the highest boiling point Tungsten
Element with highest density Osmium
Element with lowest density Hydrogen
Element with highest electronegativity Flourine
Element with lowest electronegativity (highest electropositivity) Francium
The first element to be produced artificially Technitium
The most corrosion resistant element (which cannot be affected by water, chemicals or acids) Iridium
The element which was discovered on the Sun before it was found on the Earth Helium
The non-metallic element which is liquid at room temperature Bromine
The metallic element which is liquid at room temperature Mercury
The most reactive element Flourine