The general answer would be molecule however some molecules prefer to exists as paired molecules and subdividing them would alter some of its chemical properties: a good example of this would be the sugars.
depends if its is a pure substance or a compound
an atom is the smallest, indivisible unit of a substance
the smallest amount of a chemical that would retain the chemical's physical properties would be a single molecule of the substance
It is the molecule of that compound. The compound cannot cannot be broken further so that it doesn't loose its properties.
molecule
molecule
A
I
when 2 or more compounds react chemically to form a new compound then it is called chemical reaction chemical reaction whereas the quantity and no. chemical elements presents in chemical compound is called the chemical composition
physical quantity
Put semen in liquid nitrogen.
This is the quantity of energy needed to maintain all substances involved in a chemical reaction at the same temperature.
This NOT an element, but an organic compound. CH2O is the empirical/molecular formula for methanal , formerly known as formaldehyde. Methanal is a member of the homologous series known as aldehydes. the chemical formula for aldehydes is ALWAYS written as XCHO. Hence for methanal it is HCHO NOT CH2O NB Note the 'A' in the name. NNB Ethanal formula is CH3CHO NNNB An element is a quantity/mass of the atom. Two or more atoms combined make a compound.
Chlorine
Chemical formulas consist of chemical symbols and numbers. The symbols represent the elements in the compound. The numbers indicate the quantity of atoms of each element in the compound.
when 2 or more compounds react chemically to form a new compound then it is called chemical reaction chemical reaction whereas the quantity and no. chemical elements presents in chemical compound is called the chemical composition
- francium is extremely radioactive- the total quantity of francium on the Earth is approx. 30 g- the chemical and physical properties of francium are only estimated, not measured
A good note is to remember a chemical substance is a pure form of matter. A chemical element is pure chemical substance consisting of once type of atom distinguished by it's atomic number (quantity of protons within an atom's nucleus.)Where as a chemical compound is a pure chemical substance consisting of two or more chemical element.
density, melting point, boiling point, chemical composition, electrical properties, thermal properties and the others
Mechaqnical properties are physical properties of materials.
An identification of the atoms is a molecule (APEX)
A tarrif is an quantity and value based trade restriction. In compound tarrifs, a value based tarrif is payed along with a fixed rate on quantity. That is it is a mixed or compound rate.
They only have a magnitude , no direction.
quantity, quality and direction
physical quantity