Let's break this down -
Allowance - "a sum granted as a reimbursement or bounty or for expenses ". How much you get is up to your parents, but it sounds like it may be up for negotiation. You should discuss what your allowance is for exactly. Is it for reimbursement for "chores" (which chores specifically) or is it for expenses (i.e. clothes, movies, games, etc). Do your parents give you money if you want to go out with friends? Need or want clothes? Want a new game, music, toy?
Chores - The others are right. Everyone in the household is responsible to do their share and pick up after themselves. Cleaning your room, taking care of the dog, laundry, clean the bathroom, and making your snacks fall under this category.
Taking out the trash, dusting, mopping, and sweeping are middle ground. It isn't all your mess, but it does need to be done. I would consider these "chores". All outside yard work would also fall under this category.
Cooking all the meals, setting the table, AND doing all the dishes is excessive IF you are doing this for more than just yourself (i.e. serving your parents AND picking up after them too). Sorting the coupons is a surprising responsibility. Are you cutting the coupons too. It seems like your parents could/should probably just handle this themselves.
I am also going to ask, What are your parents doing to help out around the house, exactly?
Your parents might (I would assume) have 9 to 5 jobs, but so do you. Your job is to go to school, do your homework, study, get good grades, AND have a social life. You are 12 and a kid. The house work should be SHARED because you all are busy. If you are spending two hours a day on chores, then you have too many for one day.
In conclusion, is you allowance for (fair) compensation for the chores you do? Or is it for spending money? Is it supposed to fund all your "needs" (clothes, shoes, etc.) AND "wants" (movies, outings with friends, etc.)? Unfortunately, fair or not, what your parents say, goes. Personally, what is expected of you, as portrayed, sounds unfair. If your allowance is up for negotiation, get a game plan and figure out what seems fair to you. Maybe no more than an hour of housework a day, extra money you can earn for the "chores" (as decided between you and your parents), or an hourly rate. Even at $1.00 an hour, seven days a week, that would be $14 a week.
Good luck to you all!