why do some elements have many stable isotopes with different mass numbers, while others have only one or none?

The atomic number is equal to the number of protons in the atom, therefore silicon ... What would happen to the atomic number and mass number? It would be an ... ... 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 ... Mass number of the most abundant isotope of the element with atomic number Z ... number equal to n. If there is no stable isotope, choose the one with ... As the number of neutrons in an atom increases or decreases, the isotopes tend to become more and more unstable until they get to the point where they decay ... 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 state of a gas is defined by various properties which we can observe with our senses, including the gas pressure (p), temperature (T), mass (number of ... 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 ... Experiment 1 Kendall's tau rank correlation between female or male mass, and the number and mass of ... those variables that had equal variances and were normally ... ... 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 ... ... mass number - isotopes - atomic mass unit - Bohr / Rutherford atomic model. ... equal measure to the formulation of the final grade. At the end, the ...