tailieunhanh - Project Gutenberg Etext of An Introduction to Chemical Science by R.P. Williams

Chemical substances are often called 'pure' to set them apart from mixtures. A common example of a chemical substance is pure water; it has the same properties and the same ratio of hydrogen to oxygen whether it is isolated from a river or made in a laboratory. Other chemical substances commonly encountered in pure form are diamond (carbon), gold, table salt (sodium chloride) and refined sugar (sucrose). However, simple or seemingly pure substances found in nature can in fact be mixtures of chemical substances. For example, tap water may contain small amounts of dissolved sodium chloride and compounds containing iron,. | Project Gutenberg Etext of An Introduction to Chemical Science by . Williams Copyright laws are changing all over the world be sure to check the laws for your country before redistributing these files Please take a look at the important information in this header. We encourage you to keep this file on your own disk keeping an electronic path open for the next readers. Please do not remove this. This should be the first thing seen when anyone opens the book. Do not change or edit it without written permission. The words are carefully chosen to provide users with the information they need about what they can legally do with the texts. Welcome To The World of Free Plain Vanilla Electronic Texts Etexts Readable By Both Humans and By Computers Since 1971 These Etexts Are Prepared By Thousands of Volunteers Information on contacting Project Gutenberg to get Etexts and further information is included below including for donations. The Project Gutenberg Literary .