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. Carbon-12 has 6 protons and 6 neutrons, while Carbon-14 has 6 protons and 8 neutrons. The difference in the number of neutrons gives these isotopes different atomic masses. Isotopes of an element have similar chemical properties but may have different physical properties, such as radioactive decay.
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 16 and the proton number is 8. Subtracting 8 from 16 gives us 8, which is the number of neutrons in the oxygen atom.
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 (which is 1, since they are all hydrogen atoms). However, they differ in the number of neutrons they have. Neutrons are subatomic particles with no charge, and each isotope of hydrogen has a different number of neutrons. Therefore, 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
The nucleon number represents the total number of protons and neutrons in an atom's nucleus. Since the nucleon numbers for elements P and S are different, it means they have different numbers of protons and neutrons. Therefore, the correct answer is the number of neutrons, as it is the only option that remains the same for both elements.
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
Vanadium, with a nucleon number of 51 and a proton number of 23, has 23 electrons. The nucleon number represents the total number of protons and neutrons in an atom's nucleus, while the proton number represents the number of protons. Since electrons have a negative charge and protons have a positive charge, an atom is electrically neutral, meaning it has an equal number of protons and electrons. Therefore, Vanadium has 23 electrons. The number 79 is not relevant to the question and does not represent the number of electrons in Vanadium.
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 that has one neutron in its nucleus. Since the question asks for the number of neutrons in deuterium, 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
Element X has a nucleon number of 40 and a proton number of 20. The nucleon number represents the total number of protons and neutrons in the nucleus of an atom. Since the proton number of X is 20, it means that X has 20 protons. The periodic table is arranged in order of increasing proton number, so X with 20 protons would be found in Period 2, where elements with proton numbers ranging from 3 to 20 are located.
8.
How many electrons does an isotope of Oxygen, nucleon number 16 and proton number 8, have?
Correct Answer
C. 10
Explanation
The isotope of Oxygen with a nucleon number of 16 and a proton number of 8 has 8 electrons. However, the question asks for the number of electrons an isotope of Oxygen with these specific numbers has, which is 10.
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 correct answer is "Isotopes are elements that have the same number of protons and different number of neutrons." This sentence is correct because isotopes are defined as elements that have the same number of protons (which determines the atomic number and the identity of the element) but different numbers of neutrons (which determines the atomic mass and the isotopic variant of the element).
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 will not bend or deviate when fired through an electric field because they have no charge. Protons and electrons, on the other hand, have positive and negative charges respectively, and will experience forces in the electric field that cause them to bend or deviate.