How long do you cook 4.5lb chicken?

To cook 4.5lb chicken, you will need to roast it at 350 degrees Fahrenheit for about 1 hour and 30 minutes to 1 hour and 40 minutes. It is important to make sure that the chicken is cooked all the way through, and you can check this by inserting a meat thermometer into the thickest part of the chicken. The chicken should be cooked when it reaches an internal temperature of 165 degrees Fahrenheit.