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Isotopes 10/29/2008. Isotopes 10/29/2008. Isotopes 10/29/2008. Isotopes 10/29/2008. Isotopes 10/29/2008. Isotopes 10/29/2008. Isotopes 10/29/2008. Isotopes 10/29/2008. Isotopes 10/29/2008.
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Review • Atomic Number = ______________
Review • Atomic Number = # protons • Atomic Mass = _______________
Review • Atomic Number = # protons • Atomic Mass = # protons + # neutrons • Neutrons = __________________
Review • Atomic Number = # protons • Atomic Mass = # protons + # neutrons • Neutrons = Atomic Mass – # protons
Isotopes 10/29/08 Review Atomic Number = Protons Atomic Mass = Protons + Neutrons Neutrons = Atomic Mass – Protons • In an uncharged atom, the number of protons is the same as the number of ____________. • electrons • An uncharged atom has NO charge. Why? • Protons = electrons
Isotopes What is the difference between these 2 atoms? Are they the same element?
Isotopes • There can be different types (varieties) of an element • An isotope is a different form of an element but with a different number of neutrons • Same # of protons (same atomic number)
Isotopes • If the number of neutrons is different, what else is different about the element? • Atomic Mass = protons + neutrons • If the number of neutrons is different, the atomic mass is also different
Isotopes 10/29/08 Review Atomic Number = Protons Atomic Mass = Protons + Neutrons Neutrons = Atomic Mass – Protons Isotopes Different forms of an element - Element with different # of neutrons - Atomic number is still the same • In an uncharged atom, the number of protons is the same as the number of ____________. • electrons • An uncharged atom has NO charge. Why? • Protons = electrons
Isotopes • Not all elements have isotopes • If isotopes exist, the most common form of the element is the one found on the periodic table
Isotopes 10/29/08 Review Atomic Number = Protons Atomic Mass = Protons + Neutrons Neutrons = Atomic Mass – Protons Isotopes Different forms of an element - Element with different # of neutrons - Atomic number is still the same - # of proton is the same - Atomic Mass is different - most common form found on periodic table • In an uncharged atom, the number of protons is the same as the number of ____________. • electrons • An uncharged atom has NO charge. Why? • Protons = electrons
Isotope Symbols • Isotopes are abbreviated with the element and the atomic mass • Example: Helium-3 (He-3) the atomic mass is 3 how many neutrons does it have? Atomic mass – protons 3 – 2 = 1
Isotopes 10/29/08 Representing Isotopes Element + Atomic Mass EX. Helium-3 • In an uncharged atom, the number of protons is the same as the number of ____________. • electrons • An uncharged atom has NO charge. Why? • Protons = electrons
Isotopes 10/29/08 Representing Isotopes Element + Atomic Mass EX. Helium-3 Examples EX 1: Hawkium-10 (Hk) has an atomic number of 5 and a mass number of 10. • # protons: • In an uncharged atom, the number of protons is the same as the number of ____________. • electrons • An uncharged atom has NO charge. Why? • Protons = electrons
Isotopes 10/29/08 Representing Isotopes Element + Atomic Mass EX. Helium-3 Examples EX 1: Hawkium-10 (Hk) has an atomic number of 5 and a mass number of 10. • # protons: 5 • # electrons: • In an uncharged atom, the number of protons is the same as the number of ____________. • electrons • An uncharged atom has NO charge. Why? • Protons = electrons
Isotopes 10/29/08 Representing Isotopes Element + Atomic Mass EX. Helium-3 Examples EX 1: Hawkium-10 (Hk) has an atomic number of 5 and a mass number of 10. • # protons: 5 • # electrons: 5 • # neutrons: • In an uncharged atom, the number of protons is the same as the number of ____________. • electrons • An uncharged atom has NO charge. Why? • Protons = electrons
Isotopes 10/29/08 Representing Isotopes Element + Atomic Mass EX. Helium-3 Examples EX 1: Hawkium-10 (Hk) has an atomic number of 5 and a mass number of 10. • # protons: 5 • # electrons: 5 • # neutrons: 5 • In an uncharged atom, the number of protons is the same as the number of ____________. • electrons • An uncharged atom has NO charge. Why? • Protons = electrons
Isotopes 10/29/08 Examples EX 2: Hawkium-12 (Hk) has an atomic number of 5 and a mass number of 12. • # protons: • # electrons: • # neutrons: • In an uncharged atom, the number of protons is the same as the number of ____________. • electrons • An uncharged atom has NO charge. Why? • Protons = electrons
Isotopes 10/29/08 Examples EX 2: Hawkium-12 (Hk) has an atomic number of 5 and a mass number of 12. • # protons: 5 • # electrons: • # neutrons: • In an uncharged atom, the number of protons is the same as the number of ____________. • electrons • An uncharged atom has NO charge. Why? • Protons = electrons
Isotopes 10/29/08 Examples EX 2: Hawkium-12 (Hk) has an atomic number of 5 and a mass number of 12. • # protons: 5 • # electrons: 5 • # neutrons: • In an uncharged atom, the number of protons is the same as the number of ____________. • electrons • An uncharged atom has NO charge. Why? • Protons = electrons
Isotopes 10/29/08 Examples EX 2: Hawkium-12 (Hk) has an atomic number of 5 and a mass number of 12. • # protons: 5 • # electrons: 5 • # neutrons: 7 How do we know that Hawkium-12 and Hawkium-10 are isotopes? Hawkium-12 and Hawkium-10 are isotopes - same atomic number - different atomic mass different # neutrons • In an uncharged atom, the number of protons is the same as the number of ____________. • electrons • An uncharged atom has NO charge. Why? • Protons = electrons
PRACTICE • Find the following information for Nitrogen-13, Nitrogen-14, and Nitrogen-15 • Atomic Number: • Atomic Mass: • # Protons: • # Electrons: • # Neutrons: • Which isotope is the most common form of Nitrogen?