Question

atomic structure & isotope worksheet

1. the mass of an atom is contained mainly in its __ and __.
2. the identity of an element is determined by its number of ____.
3. isotopes are atoms with the same number of ____ and different number of neutrons
4. the charge of an atom or ion is determined by its number of ____.
5. what is the central core of an atom called?

a) electron b) isotope c) nucleus d) proton

1. an atom with a charge is known as an

a) isotope b) isomer c) element d) ion

1. an atom with equal number of protons and electrons is called

a) isotope b) neutral atom c) ion d) nucleus

1. isotopes have

a) same number of neutrons b) different number of neutrons
c) different number protons d) different number of electrons

1. an isotope of carbon is

a) boron - 12 b) nitrogen - 12 c) carbon - 14 d) hydrogen - 2

1. the table below contains information about several elements. in each case, enough information has been provided for you to fill in the blanks.

protons	neutrons	electrons	element name	is it an ion? if so, what is the charge?	nuclear symbol
15	17	15
12	12	12
12	13	12
28	32	27

chemistrylearner.com

Explanation:

1. The mass of an atom is mainly in its protons and neutrons as they are much heavier than electrons.
2. The identity of an element is determined by its number of protons.
3. Isotopes have the same number of protons and different numbers of neutrons.
4. The charge of an atom or ion is determined by the difference between the number of protons and electrons.
5. The central core of an atom is the nucleus.
6. An atom with a charge is an ion.
7. An atom with equal number of protons and electrons is a neutral atom.
8. Isotopes have different numbers of neutrons.
9. Carbon - 14 is an isotope of carbon.

10.

• For 47 protons, 63 neutrons, 47 electrons: Element name is silver (Ag), not an ion, nuclear symbol is $^{110}_{47}Ag$.
• For 15 protons, 17 neutrons, 15 electrons: Element name is phosphorus (P), not an ion, nuclear symbol is $^{32}_{15}P$.
• For 12 protons, 12 neutrons, 12 electrons: Element name is magnesium (Mg), not an ion, nuclear symbol is $^{24}_{12}Mg$.
• For 12 protons, 13 neutrons, 12 electrons: Element name is magnesium (Mg), not an ion, nuclear symbol is $^{25}_{12}Mg$.
• For 28 protons, 32 neutrons, 27 electrons: Element name is nickel (Ni), is an ion with a + 1 charge, nuclear symbol is $^{60}_{28}Ni^{+}$.

Answer:

1. protons; neutrons
2. protons
3. protons
4. difference between protons and electrons
5. c) nucleus
6. d) ion
7. b) neutral atom
8. b) different number of neutrons
9. c) carbon - 14

10.

• silver (Ag); No; $^{110}_{47}Ag$
• phosphorus (P); No; $^{32}_{15}P$
• magnesium (Mg); No; $^{24}_{12}Mg$
• magnesium (Mg); No; $^{25}_{12}Mg$
• nickel (Ni); Yes, + 1; $^{60}_{28}Ni^{+}$