There are no Chinese alphabet! The Chinese written words are called characters. The characters are composed of different shapes of lines called strokes.You might argue that you definitely have seen the alphabet used for learning Chinese. Well, those are the letters of the alphabet for sure, but used in a very different way, and this special way even has a special name for it. The alphabet letters are only used to "spell out the sounds", so it is used as a phonetic system to aid the learning of Chinese. This system is called "Pinyin", literally means piecing sounds. Many letters are pronounced very differently ( such as c, q, r, x, z), and there are also some very uncommon combinations (zh).
Pinyin is helpful for most adults learning Chinese. It provides information for retrieving the pronunciation for a character because there is virtually no way to pronounce a character simply by looking at it. Many children in the U.S. enrolled in Chinese immersion schools are able to learn characters without knowing Pinyin from the start.
Chinese is a tonal language. Pinyin for that matter, should include the tones indicated by "tone marks". Yet many Chinese expressions, when spelled out in Pinyin for non-Chinese, do not include the tone marks. Sometimes the tones are added with numbers 1-4 into the spelling.