Atoms with the same number of protons but different

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Atoms with the same number of protons but different numbers of neutrons are called isotopes . Some elements only have one naturally occurring isotope, while others such as carbon have two or more. In a naturally occurring sample, isotopes of each element are present in a certain percentage amount called the percent natural abundance . The mass number of an isotope is the sum of the number of protons and the number of neutrons for a particular isotope and is symbolized by . There are several different types of isotope notation. For example, a carbon isotope that has an atomic number of 6 and a mass number of 13 could be symbolized in any of the following ways: , carbon-13, or -13. Part A Enter the appropriate symbol for an isotope of calcium-42 corresponding to the isotope notation . Express your answer as a chemical symbol using isotope notation. Hint 1. How to interpret isotope notation There are several common notations used for isotopes, including where represents the mass number, represents the atomic number, and represents the chemical symbol; and - where represents the chemical symbol or name of the element and represents the mass number. Hint 2. Determine the atomic number of calcium-42 What is the atomic number of calcium-42? Express your answer numerically as an integer. Hint 1. How to determine the atomic number Each element has a unique atomic number, which is equal to the number of protons in the nucleus of an atom. The periodic table of elements is arranged by the atomic number of the elements. For a given element, look above the symbol in the periodic table to find the atomic number. For example, carbon has an atomic number of 6. ANSWER: ANSWER: Correct An isotope of calcium, calcium-42, can be symbolized as shown here: . Part B Complete the following chart: Drag each label to the appropriate target. Hint 1. Determine the number of protons for an example atom How many protons does neon-21 contain? A A = number of protons + number of neutrons C 13 6 C X A Z X A Z A Z X X A X A 20 Ca 42 20 Ca 42 20
Express your answer numerically as an integer. Hint 1. How to determine the number of protons Each element has a unique atomic number, which is equal to the number of protons in the nucleus of an atom. The periodic table of elements is arranged by the atomic number of the elements. For a given element, look above the symbol in the periodic table to find the atomic number. For example, carbon has an atomic number of 6. Hint 2. Determine the number of neutrons for an example atom How many neutrons does neon-21 contain? Express your answer numerically as an integer. Hint 1. How to determine the number of neutrons In the isotope notation given here, neon-21, the number 21 represents the mass number of the isotope. The mass number is determined by the equation shown here: You can rearrange this equation to solve for the number of neutrons. Hint 3.