1.
Carbon-12 and Carbon-14 are _______________.
Correct Answer
B. Isotopes
Explanation
Carbon-12 and Carbon-14 are isotopes. Isotopes are atoms of the same element that have different numbers of neutrons in their nucleus, resulting in different atomic masses. Carbon-12 has 6 protons and 6 neutrons, while Carbon-14 has 6 protons and 8 neutrons. Despite having different atomic masses, isotopes of an element have similar chemical properties because they have the same number of protons, which determines the element's identity.
2.
The atom oxygen has a neucleon number of 16 and a proton number of 8. what is the number of neutrons in the oxygen atom?
Correct Answer
C. 8
Explanation
The number of neutrons in an atom can be calculated by subtracting the proton number from the nucleon number. In this case, the nucleon number is given as 16 and the proton number is given as 8. Therefore, the number of neutrons in the oxygen atom is 8.
3.
Hydrogen, deuterium and tritium are all isotopes of hydrogen. They have a different number of _____________.
Correct Answer
B. Neutrons
Explanation
Hydrogen, deuterium, and tritium are all isotopes of hydrogen, meaning they have the same number of protons (one) but different numbers of neutrons. Since the question asks for the "different number," the correct answer is neutrons.
4.
Element P has a nucleon number of 31 and a proton number of 15. Eement S has a nucleon number of 32 and a proton number of 16. The two elements have the same __________.
Correct Answer
B. Number of neutrons
Explanation
Element P has a nucleon number of 31 and a proton number of 15, which means it has 16 neutrons (31 - 15 = 16). Element S has a nucleon number of 32 and a proton number of 16, which means it also has 16 neutrons (32 - 16 = 16). Therefore, the two elements have the same number of neutrons.
5.
Vanadium, V has a nucleon number of 51 and a proton number of 23. how many electrons does it have?
Correct Answer(s)
B. 79
D. 23
Explanation
The nucleon number of an element represents the total number of protons and neutrons in its nucleus. In this case, Vanadium (V) has a nucleon number of 51, which means it has 51 protons and neutrons combined. The proton number, also known as the atomic number, represents the number of protons in the nucleus. Vanadium has a proton number of 23, indicating that it has 23 protons. Since atoms are electrically neutral, the number of electrons in an atom is equal to the number of protons. Therefore, Vanadium has 23 electrons.
6.
Hydrogen has a nucleon number of 1 and a proton number of 1. how many neutrons does deuterium, an isotope of hydrogen, have?
Correct Answer
D. 1
Explanation
Deuterium is an isotope of hydrogen, which means it has the same number of protons (1) but a different number of neutrons. Since the nucleon number of hydrogen is 1 and deuterium has 1 neutron, the correct answer is 1.
7.
Element X has a nucleon number of 40 and a proton number of 20. Which period in the periodic table is X found in?
Correct Answer
A. Period 2
Explanation
The nucleon number of an element is equal to the sum of its protons and neutrons. Since element X has a nucleon number of 40 and a proton number of 20, it must have 20 neutrons. Based on the periodic table, elements in period 2 have atomic numbers ranging from 3 to 10, which means they have nucleon numbers ranging from 7 to 20. Therefore, element X with a nucleon number of 40 and a proton number of 20 cannot be found in period 2.
8.
How many electrons does an isotope of Oxygen, nucleon number 16 and proton number 8, have?
Correct Answer
C. 10
Explanation
The nucleon number of an atom represents the total number of protons and neutrons in its nucleus. In this case, the nucleon number of the isotope of Oxygen is 16. Since the proton number is 8, we can determine that there are 8 protons in the nucleus. Since the atom is neutral, the number of electrons is equal to the number of protons. Therefore, the isotope of Oxygen has 8 electrons.
9.
“Isotopes are elements that have the same number of neutrons and different number of protons.” What is wrong with the previous sentence?
Correct Answer
A. Isotopes are elements that have the same number of protons and different number of neutrons.
Explanation
The previous sentence is incorrect because it states that isotopes have the same number of neutrons and different number of protons, whereas in reality, isotopes have the same number of protons and different number of neutrons.
10.
A beam of particles containing protons, neutrons and electrons is fired through an electric field. Which particle will not bend or deviate?
Correct Answer
C. Neutron
Explanation
Neutrons do not have an electric charge, unlike protons and electrons. When a beam of particles is fired through an electric field, charged particles will experience a force and be deflected or bent. However, since neutrons have no charge, they will not be affected by the electric field and will not bend or deviate from their path.