1.The meaning of atomos is ….
2.An atom is the … of an element that retains the properties of that element.
3.The concept of an atom was first suggested by an ancient Greek named Democritus. He theorized that if you took an object and cut it in half again and again you would eventually end up with some particle which ….
a.could be divided
b.could not be divided
c.could be further divided
d.could not be further divided
e.could not further divide
4.One of the following statements about an atom is wrong, except ….
a.is not neutral
b.has negative charge
c.is positively charged
d.the smallest particle
e.has a variable charge
5.Which one of the following statements is not true about the nucleus of an atom ?
a.It is located at the centre of the atom
b.Its relative mass is nucleon number
c.It always has an equal number of protons and neutrons
d.The mass of an atom is concentrated in the nucleus
e.It has a negative charge
6.The following statements are true about a neutral atom, except ….
a.the number of electrons equals the number of protons
b.the number of neutrons equals the atomic number
c.the number of neutrons equals the mass number minus the atomic number
d.the atomic number indicates the number of protons
e.the mass number equals the number of neutrons and protons
7.How many neutrons are there in a 238-U atom (atomic number 92)?
8.How many neutrons are there in a 1-H atom?
9.In which group do the particles contain only nucleons?
a.protons and electrons
b.neutrons and electrons
c.protons and neutrons
d.protons, neutrons, and electrons
10.An atom of fluorine has a mass of 19 atomic mass units. The total number of protons and neutrons in its nucleus is ….
11.What is the atomic number of an element that has six protons and eight neutrons?
12.What is the mass number of an atom which contains 28 protons, 28 electrons, and 34 neutrons?
13.How many electrons are there in the Mg2+ ion?
14.How many positive particles are there in the Na+ ion?
15.If a metal becomes ion, so ….
a.the number of electrons increase
b.the number of neutrons decrease
c.the number of protons decrease
d.the ion has a positive charge
e.the atom changes into anion
16.The number of neutrons in the nucleus of an atom can be determined by ….
a.adding the atomic number to the mass number
b.subtracting the atomic number from the mass number
c.adding the mass number to the atomic mass
d.subtracting the mass number from the atomic number
17.The correct answer about carbon atom, 6C (12,011) is ….
a.carbon atom has 12 protons
b.carbon's mass number is 6
c.carbon’s atomic mass is 12.011 amu
d.carbon's most common isotope has 7 neutrons
e.all isotopes have the same numbers of neutrons
18.The wrong answer about nitrogen, 7N (14,007) is ….
a.the number of electron is 7
b.an average mass is 14.007 amu
c.one of the isotope has a mass of 14 amu
d.the mass number equals the number of neutrons
e.an isotope of N atom has 7 protons, 7 neutrons and 7 electrons
19.Which statement about the mass of an electron is correct?
a.The mass of an electron is equal to the mass of a proton.
b.The mass of an electron is less than the mass of a proton.
c.The mass of an electron is equal to the mass of a neutron.
d.The mass of an electron is greater than the mass of a neutron.
20.Atoms of the same element that have different numbers of neutrons are classified as ….
21.The following information are about three isotopes of carbon, 6C:
1.C-12, mass = 12
2.C-13, mass = 13
3.C-14, mass = 14.
Based on the above data, the correct answer is ….
a.carbon – 12 has the same numbers of protons and neutrons
b.carbon – 13 has the smallest numbers of neutrons
c.the heavy atom is carbon with the smallest numbers of neutrons
d.all isotopes have the same number of protons and neutrons
e.the atomic mass of carbon is more than 14 amu