1.
How many electrons are in a Hydrogen (H) atom?
Correct Answer
A. One
Explanation
A Hydrogen atom consists of one electron. The atomic number of Hydrogen is 1, indicating that it has one proton in its nucleus. The number of electrons in an atom is equal to the number of protons in a neutral atom; therefore, a Hydrogen atom has one electron.
2.
How many neutrons in a Hydrogen (H) atom?
Correct Answer
A. Zero
Explanation
A hydrogen atom consists of one proton and one electron. Neutrons are not present in the most common hydrogen isotope
3.
What do the letters "amu" stand for?
Correct Answer
B. Atomic Mass Unit
Explanation
The letters "amu" stand for Atomic Mass Unit. This unit is used to express the mass of atoms and molecules. It is defined as one-twelfth the mass of a carbon-12 atom. The atomic mass unit is commonly used in chemistry and physics to compare the masses of different atoms and molecules.
4.
If an atom has 13 electrons, how many shells will have electrons?
Correct Answer
C. Three
Explanation
If an atom has 13 electrons, it will have three shells. The first shell can hold a maximum of 2 electrons, the second shell can hold a maximum of 8 electrons, and the third shell can hold a maximum of 18 electrons. Since the atom has 13 electrons, it means that the first shell will have 2 electrons, the second shell will have 8 electrons, and the third shell will have 3 electrons. Therefore, the atom will have three shells with electrons.
5.
What will happen to the pressure inside of a sealed tube if you raise the temperature?
Correct Answer
A. Go Up
Explanation
When the temperature inside a sealed tube is raised, the particles of gas inside gain more kinetic energy and move faster. This increased motion results in more frequent and forceful collisions between the gas particles and the walls of the tube. As a result, the pressure inside the tube increases. Therefore, the correct answer is "Go Up."
6.
What is the name of the compound NaCl?
Correct Answer
D. Sodium chloride
Explanation
The correct answer is sodium chloride because NaCl is the chemical formula for sodium chloride. Sodium chloride is a compound made up of sodium ions (Na+) and chloride ions (Cl-). It is commonly known as table salt and is used in various applications, including as a seasoning for food and in the production of chlorine and sodium hydroxide.
7.
If you pour liquid nitrogen (N2) into a glass, it will change its state to a solid.
Correct Answer
B. False
Explanation
When liquid nitrogen (N2) is poured into a glass, it does not change its state to a solid. Liquid nitrogen is extremely cold, with a boiling point of -195.79 degrees Celsius. As a result, liquid nitrogen is poured at room temperature, and pressure quickly evaporates into nitrogen gas. It only changes to a solid state when it is exposed to temperatures below its freezing point of -210 degrees Celsius. Therefore, pouring liquid nitrogen into a glass will not cause it to solidify.
8.
Plasmas are all made of the same ions. They have different colors due to different amounts of electricity.
Correct Answer
B. False
Explanation
The statement is false because plasmas are not all made of the same ions. Plasmas can be made up of different combinations of ions, depending on the specific conditions and materials involved. The different colors observed in plasmas are not solely due to different amounts of electricity, but rather the specific ions present and the energy levels at which they emit light.
9.
Name the forces that keep molecules together when the surrounding energy drops.
Correct Answer
C. Attraction
Explanation
When the surrounding energy drops, molecules are kept together by the force of attraction. This force occurs between the positive and negative charges of different molecules or between atoms within a molecule. This attraction force helps to maintain the stability and structure of the molecules, preventing them from breaking apart.
10.
Which is an example of a crystal lattice?
Correct Answer
B. Diamond
Explanation
Diamond is an example of a crystal lattice because it is a highly ordered and repeating arrangement of carbon atoms. In a crystal lattice, the atoms or molecules are arranged in a regular pattern, forming a three-dimensional structure. Diamond has a well-defined crystal structure, with each carbon atom bonded to four neighboring carbon atoms in a tetrahedral arrangement. This regular arrangement gives diamond its characteristic hardness and optical properties. Plastic, cement, and sand do not have a crystal lattice structure.