Question

please help i am in trouble ​

Answer 1

Define atom:The atom is the smallest object that retains the properties of an element.Atoms are composed of electrons and a nucleus. The nucleus contains protons and neutronsAll atoms are electrically neutral, because every atom has an equal number of electrons and protons.

Nearly all of the atom's mass is located in the nucleus. The nucleus is tiny compared with the total size of the atom. Most of the atom's volume holds the electron cloud, whose mass is tiny. Atoms are generally spherical, although there are indications that atoms of the very heaviest elements may exist as squashed spherical shapes. An atom's chemical behavior is determined by the arrangement of its electrons. Atoms may combine with one another by chemical bonding to produce molecules. They may also ionize to form ionic compounds.

Define Molecule:A molecule is a particle made up of two or more atoms that are chemically bonded together; the number of atomic nuclei making up a molecule is a determinate number. For example, HCl(g) is a molecule made of one hydrogen atom bonded to one chlorine atom. It is made of two atoms and is called a diatomic molecule.A crystal of NaCl(s) is not a molecule: it is an ionic lattice made up of an indeterminate number of atoms. Carbon dioxide is a molecule made of two oxygen atoms bonded to a carbon atom. It contains three atoms and is called a triatomic molecule.

Silicon dioxide - best known as quartz - exists as an large covalent network made up of an indeterminate number of atoms.

One of the most abundant triatomic molecules in the universe is the trihydrogen cation H3+. Although plentiful in space, where it is stabilized by the very low temperature and the low density of matter, the trihydrogen cation is rare on Earth. Very large molecules exist; they are known as macromolecules. An example of a particularly large macromolecule is DNA, which contains hundreds of billions of atoms.

Sorry! i have only tow defination

Answer 2

table 4.9 : some common compounds ,---- their state formulae and elements present in them,