Stemscopes Exam Chemistry Fundamentals 1 — Questions and Answers
Question 1: What is the atomic number of an element?
- Number of neutrons
- Number of protons (Correct answer)
- Number of electrons + protons
- Mass of the atom
Correct answer: Number of protons
The atomic number is the number of protons in the nucleus of an atom, which defines the element.
Question 2: Which subatomic particle has no charge?
- Proton
- Electron
- Neutron (Correct answer)
- Ion
Correct answer: Neutron
Neutrons are subatomic particles found in the nucleus that carry no electrical charge.
Question 3: What type of bond involves the sharing of electrons between atoms?
- Ionic bond
- Covalent bond (Correct answer)
- Metallic bond
- Hydrogen bond
Correct answer: Covalent bond
Covalent bonds form when two atoms share one or more pairs of electrons.
Question 4: What is the chemical formula for water?
- HO
- H2O (Correct answer)
- H2O2
- OH
Correct answer: H2O
Water consists of two hydrogen atoms covalently bonded to one oxygen atom, giving the formula Hâ‚‚O.
Question 5: In a chemical reaction, what are the starting materials called?
- Products
- Reactants (Correct answer)
- Catalysts
- Compounds
Correct answer: Reactants
Reactants are the substances that enter a chemical reaction and are transformed into products.
Question 6: What does the law of conservation of mass state in a chemical reaction?
- Mass is created during reactions
- Mass is destroyed during reactions
- The total mass of reactants equals the total mass of products (Correct answer)
- Mass can be lost as energy
Correct answer: The total mass of reactants equals the total mass of products
The law of conservation of mass states that matter is neither created nor destroyed in a chemical reaction.
Stemscopes Exam Chemistry Fundamentals 1
What is the atomic number of an element?