The atoms within a compound can be held together by a variety of interactions, ranging from covalent bonds to electrostatic forces in ionic bonds. A continuum of bond polarities exist between the purely covalent bond (as in H2) and ionic bonds. For example H2O is held together by polar covalent bonds. Sodium chloride is an example of an ionic compound. Formation of a compound involves a chemical reaction, whereas a mixture can be created simply by the physical act of stirring items together.
The French will tell you it's all down to the "terroir". Wine can vary between rows of vines, depending on the soil, the elevation, the drainage, the amount of sunlight, even the wind. Some of it may also be down to the skill or ideas of the winemakers themselves.
In a chemical reaction, the law of conservation of mass must be followed: no matter may be destroyed OR created (the mass cannot change). In writing chemical equations, the mass of the left side must equal the mass on the right side. This also must be true of the number of each element. To follow the law of conservation of mass, coefficients must be used. Coefficients do NOT change the formula, just the relative amount of each substance (number of moles present). Example: Hydrogen gas (H2) and oxygen gas (O2) react to form water (H2O). H2+O2 -> H2O (this equation is not balanced as there are 2 oxygen on the left and 1 on the right) --multiply H2O by 2 H2+O2 -> 2H2O (not balanced as there are 2 hydrogen on the left and 4 on the right) --multiply H2 by 2 2H2+02 -> 2H2O (balanced equation)
No, there are bases that are just as strong as some of the most powerful acids. Looking at the pH scale, the further away from 7 (neutral) you get on either end, the stronger the acid or base is.There are also many other chemicals, that are neither acids nor bases, that are extremely dangerous! For instance, mercury is toxic. Other compounds, such as chlorine gas are extremely corrosive and will burn skin and cause severe respiratory problems. Many other compounds are dangerous and can cause problems like cancer and other serious illness if exposed to even small amounts.