1.
About how many atomic numbers are there?
Correct Answer
A. 100
Explanation
There are 100 atomic numbers.
2.
About how many compounds are there?
Correct Answer
C. Far greater than 10,000
Explanation
The answer "Far greater than 10,000" suggests that there are a large number of compounds. It implies that the actual number of compounds is significantly higher than both 100 and 1000. This answer indicates that the number of compounds is extensive and exceeds the other options provided.
3.
Which of the following are organic compounds?
Correct Answer(s)
B. C6H12O6
C. C2H4
Explanation
The organic compounds are C6H12O6 and C2H4 because they both contain carbon atoms. NaCl and H2O are not organic compounds because they do not contain carbon atoms.
4.
Minerals are produced...
Correct Answer
C. None of the above
Explanation
Minerals are not produced in the stomach or in the ocean. Minerals are naturally occurring substances that are found in the Earth's crust and are obtained through various sources such as plants, animals, and water. They are essential for the proper functioning of the human body and are obtained through the consumption of a balanced diet. Therefore, the correct answer is "None of the above" as neither the stomach nor the ocean is a source of mineral production.
5.
A proton ....
Correct Answer
D. None of the above
Explanation
A proton has a positive charge of +1 and is located inside the nucleus of an atom. Therefore, none of the given options accurately describe a proton.
6.
All atoms of the same elements have the same:
Correct Answer
A. Number of protons
Explanation
All atoms of the same element have the same number of protons because the number of protons determines the atomic number, which is unique to each element. The atomic number defines the identity of the element and is equal to the number of protons in the nucleus of an atom. Therefore, regardless of the isotope or the number of neutrons, all atoms of the same element have the same number of protons.
7.
A hypothesis is less supported than a theory.
Correct Answer
A. True
Explanation
A hypothesis is a proposed explanation for a phenomenon that is based on limited evidence and requires further testing to be confirmed. On the other hand, a theory is a well-substantiated explanation that has been extensively tested and supported by a large body of evidence. Therefore, a hypothesis is indeed less supported than a theory, making the statement true.
8.
A scientific theory is always absolute.
Correct Answer
B. False
Explanation
Scientific theories are not absolute but rather provisional explanations based on available evidence. They are subject to change and revision as new evidence and data emerge. The nature of scientific inquiry encourages continuous questioning and testing of theories, promoting a better understanding of the natural world. Therefore, it is incorrect to say that a scientific theory is always absolute.
9.
What are the 6 most commonly used elements in chemistry?
Correct Answer(s)
A. C
C. H
D. S
E. P
F. N
H. O
Explanation
The given answer includes the elements C (carbon), H (hydrogen), S (sulfur), P (phosphorus), N (nitrogen), and O (oxygen). These elements are commonly used in chemistry because they are abundant in nature and play important roles in various chemical reactions and compounds. Carbon is the basis of organic chemistry, hydrogen is present in many compounds, sulfur and phosphorus are essential for biological processes, nitrogen is a key component of proteins and nucleic acids, and oxygen is involved in respiration and combustion reactions.
10.
Ions are...
Correct Answer
B. Charged Particles
Explanation
Ions are charged particles because they have gained or lost electrons, resulting in an imbalance between the number of protons and electrons. This imbalance gives ions a positive or negative charge, making them attracted to other charged particles and allowing them to participate in chemical reactions.
11.
The polarity of water can cause hydrogen molecules to bond
Correct Answer
A. True
Explanation
Water is a polar molecule, meaning it has a slight positive charge on one end and a slight negative charge on the other. This polarity allows water molecules to attract and bond with each other through hydrogen bonding. Hydrogen bonding occurs when the positively charged hydrogen atom of one water molecule is attracted to the negatively charged oxygen atom of another water molecule. This bonding is responsible for many of water's unique properties, such as its high boiling point and surface tension. Therefore, the statement that the polarity of water can cause hydrogen molecules to bond is true.
12.
An atom becomes an ion when it
Correct Answer
B. Gains or loses electrons
Explanation
An atom becomes an ion when it gains or loses electrons. This is because ions are formed when atoms have an unequal number of protons and electrons. When an atom gains electrons, it becomes negatively charged and forms a negative ion (anion). On the other hand, when an atom loses electrons, it becomes positively charged and forms a positive ion (cation). Therefore, the gain or loss of electrons is the determining factor in the formation of ions.
13.
The compound CO2 represents
Correct Answer
C. One atom of carbon and two atoms of oxygen
Explanation
The compound CO2 represents one atom of carbon and two atoms of oxygen. This is because the subscript 2 in CO2 indicates that there are two atoms of oxygen bonded to one atom of carbon in the molecule.
14.
Protons move at a very fast pace/speed around the outside of the nucleus.
Correct Answer
B. False
Explanation
Protons are positively charged particles that are located inside the nucleus of an atom. They are not moving at a fast pace or speed around the outside of the nucleus. Instead, they are tightly bound within the nucleus along with neutrons. Therefore, the statement is false.