SCHEDULE CHANGE. A planned change or a flight number/time change which can occur up to more than 72 hours prior to the flight's scheduled. departure. Examples - Change of flight times, change of flight numbers, reduction of service, discontinuation of all service. in a market. American uses an automated schedule change process up to 72 hours prior to departure. Through this automated. process all schedule changes are sent to the booking source for notification.
Describe the particles that make up the nucleus of an atom in terms of mass and charge. Protons, neutrons and electrons. Protons have a relative mass of 1 and a charge of +1, they are found in the nucleus of an atom.
The atomic number, #Z#, of any element, is the number of protons, positively charged nuclear particles, contained in the nucleus. The mass number (#235#) is the sum of the number of protons, AND the number of neutrons, NEUTRALLY charged nuclear particles. Note that only protons and neutrons contribute to atomic mass to any degree. You have #^235U#. If #Z=92# how many neutrons are there? And how did I know #Z=92#?