Essay questions require yet another set of skills. The first requirement, of course, is that you be able to write in the English language. Without intending to be unfriendly or mean, I do know that there may be some who have difficulty with that. The best I can tell you for a problem with the English language is that practice definitely shows. Most instructors can easily see through that and do not grade it, except downward if it becomes excessive.
Most instructors look for content when they grade an essay test.
Chemtutor can help you keep up with the class. If you still need help, other students in your class may be able to help you. If you do not get the help you need from students, call or visit your instructor. If the other students can not help you, maybe they also need some help. Most instructors would be glad to help you on an individual or group basis.