Two or more different elements that are chemically combined in a definite ratio is a compound. Based on the nature of the bonds, it can be called an ionic compound (i.e. atoms bonded together by ionic bonds) or an molecular compound (i.e. atoms bonded together by covalent bonds).
Chemical compounds are composed of two or more different substances that are chemically combined in a definite ratio.
It Called a compound.
Either a compound or a mixture.
a compound!
compound
A compound
A pure substance is either an element or compound. Elements are composed of only one kind of atom, and compounds are composed of a definite proportion of atoms of different elements that is always the same.
Such a substance is especially called a compound.
"chemical composition" is talking about the individual chemicals that make up a substance. The chemicals it is composed of. eg, wood is mainly carbon, with some water (which is hydrogen and oxygen) and various minerals.
Gas containing two or more different kinds of molecules (or elements) always form homogeneous mixtures, like air (N2, O2, CO2, etc. etc., water and other vapours, perfumes, air-polluting gases, etc.etc.). If it is composed only with ONE kind of compound or element then it is pure.
A binary compound is formed from two different chemical elements.
A pure substance is either an element or compound. Elements are composed of only one kind of atom, and compounds are composed of a definite proportion of atoms of different elements that is always the same.
compound
A substance in which the exact combination of elements is always the same, is called a compound.
A pure substance is something like just water (H2O). A homogeneous mixture is a solution with multiple compounds. These mostly contain water, but not always. An example of a homogeneous mixture is H2O+NaCl or NaCl (aq).
Such a substance is always an element.
Such a substance is especially called a compound.
a compound
No, it depends on the substance and it's elements.
A compound is defined as a substance that contains at least two chemical elements and always has a constant mass ratio between elements for each possible pair of the elements that are present in it.
No, they can be EXTREMELY cold. It depends on the substance and what its elements are.
compound
No - a star would not be a pure substance. Our understanding of how stars function includes a continuous fusion of hydrogen to form helium and, depending on the star, possibly further fusion of the helium into even heavier elements. Once formed, these heavier elements do not just go away or change back into helium so stars will always be composed of a mixture of hydrogen and the byproducts of fusion.