Thus by 1803 there were two known rare earth elements, yttrium and cerium, although it took another 30 years for researchers to determine that other elements were contained in the two ores ceria and yttria (the similarity of the rare earth metals' chemical properties made their separation difficult).
For instance, students who pursue a Ph.D. in psychology usually take from five to seven years depending upon required coursework as well as internship and supervised residency requirements.
Ph.D. programs in experimental psychology to do not require an additional internship year. In a Psy.D. program, often referred to as a professional school program, there is greater emphasis on training and professional practice. How Long Does it Take to Become a Psychologist? Overall, it takes approximately five to eight years after receiving a bachelorâs degree to obtain a Ph.D. in psychology. A master's degree usually takes two to three years to complete, followed by an additional four to six years for a doctoral (Ph.D., Psy.D.) degree. Some schools permit students to enter a doctoral program directly from receipt of a bachelor's degree.