Stemscopes Exam Chemistry Fundamentals 2 — Questions and Answers
Question 1: How are elements arranged on the modern periodic table?
- By alphabetical order
- By increasing atomic mass
- By increasing atomic number (Correct answer)
- By date of discovery
Correct answer: By increasing atomic number
Elements on the modern periodic table are arranged in order of increasing atomic number from left to right.
Question 2: What is a mixture?
- Two or more elements chemically combined
- Two or more substances physically combined (Correct answer)
- A single pure element
- A compound with fixed ratios
Correct answer: Two or more substances physically combined
A mixture consists of two or more substances that are physically combined but not chemically bonded.
Question 3: Which of the following is an example of an exothermic reaction?
- Photosynthesis
- Burning wood (Correct answer)
- Melting ice
- Dissolving ammonium nitrate in water
Correct answer: Burning wood
Burning wood releases heat and light energy into the surroundings, making it an exothermic reaction.
Question 4: What is the pH of a neutral solution?
- 0
- 7 (Correct answer)
- 14
- 1
Correct answer: 7
A neutral solution has a pH of 7, which means the concentration of H⁺ and OH⁻ ions are equal.
Question 5: Which element is represented by the symbol 'Fe' on the periodic table?
- Fluorine
- Francium
- Iron (Correct answer)
- Fermium
Correct answer: Iron
Fe is the chemical symbol for iron, derived from the Latin word 'ferrum.'
Question 6: What is a catalyst?
- A substance consumed in a reaction
- A substance that slows down a reaction
- A substance that speeds up a reaction without being consumed (Correct answer)
- A product of a chemical reaction
Correct answer: A substance that speeds up a reaction without being consumed
A catalyst increases the rate of a chemical reaction without being permanently consumed in the process.
Stemscopes Exam Chemistry Fundamentals 2
How are elements arranged on the modern periodic table?