are there any exceptions to the rule that mass number is the sum of protons and neutrons?

... equal to Z + N (Figure 2). The mass of the nucleus in atomic mass units (amu) is usually slightly different from the mass number. Atoms of the same element ... In other words, the mass number is equal to the number of protons plus the number of neutrons in the nucleus of an atom. Using the given notation, we can ... The new angular transmission labeled “projection” method is equal to ... mass number are shown in Fig.25. The parameters of the Abrasion-Ablation ... ... equal to 75 U/mL). Data of patients in two groups were collected and evaluated such as gender, age, body mass, number of patients with chemical burn ... ... number of protons equals the number of electrons. Because these particles have the same but opposite charges, equal numbers cancel out, producing a neutral atom ... The number of neutrons in the nucleus is equal to A minus Z. chemical symbol. Two different forms, or isotopes, of carbon are shown below: Carbon-12: with 6 ... The atomic number of an element states the number of protons in the nucleus of every atom of that element. The number of electrons in an atom is equal to the ... It differs from the exact mass of the atom in atomic mass units, amu, which is often known and expressed to six decimal places. (One amu is exactly one-twelfth ... No, the mass number of an atom is not equal to the number of electrons. The mass number is the sum of the number of protons and neutrons in the nucleus of ... ... equal to 1/12 of the mass of a carbon-12 atom. Atomic number. The number of ... All nuclides with a certain mass number, but a different atomic number ...