Practice Problems 4 Chapter 2 CHE 151
Graham/07
1.) How many protons and neutrons are in the nuclei of 204Tl atoms? __________
__________
2.) What is the atomic number, mass number and symbol for the element that has
45 protons and 58 neutrons?
__________ __________ __________
3.) Write the complete symbol for an atom with the following characteristics
a.) contains 19 electrons and 20 neutrons __________
b.) nitrogen atom with 8 neutrons __________
c.) bromine atom with a mass number of 80 __________
d.) mercury atom that contains 281 subatomic particles __________
e.) contains 20 protons and has a mass number of 42 __________
f.) cobalt atom with 33 neutrons __________
g.) iodine atom with 181 subatomic particles __________
h.) sulfur atom with 52 subatomic particles __________
i.) uranium atom with 146 neutrons __________
j.) copper atom with 65 nucleons __________
4.) Magnesium occurs in nature in three isotopic forms:
relative mass
24Mg (78.70% abundance) 23.985 amu
26Mg (11.17% abundance) 25.983 amu
25Mg (10.13% abundance) 24.986 amu
Calculate the atomic mass of Magnesium from these data
