Low to Middle level taxpayers take their tax deductions seriously and want everything possible that will lower their tax burden or better yet, increase their REFUND. The National Association of Home Builders estimates that deducting MI premiums will save homeowners more than $1.3 billion per year so this is important stuff.
Sulfur and iron: since this is a mixture, the sulfur retains its properties (its yellow color, for example), and the iron retains its properties (its black color, for example). These properties can be used to separate the two elements. For iron sulfide, two elements (sulfur and iron) are heated together so that they form the compound iron sulfide. Although iron sulfide contains both sulfur and iron, it is not a mixture: it is a pure substance. Both the sulfur and the iron have âgiven upâ their individual properties to become a compound.
Yes, in chemistry a pure substance means either an element or a compound. Thus, hydrogen, oxygen, sodium, iron, copper etc. are pure substances; and so are compounds such as water, sugar, ammonia, sodium chloride, methane, ethanol etc. A compound is composed of two or more elements combined in a fixed ratio by mass. Like an element, a compound also has a distinct chemical identity. A mixture is not a pure substance as it is a collection of two or more elements/compounds in varying ratio. Air, sea water, gasoline, vegetable oils, steel etc. are mixtures.