Comprehensive Science And Practice Exam 1&2 Questions And Marking Scheme Direct Pass Graded A+ Year 2025/2026!!!!!

Comprehensive science and practice exam 1&2 questions and marking scheme direct pass graded A+ year 2025/2026!!!!! Science Test 1 ANSWER SHEET SCIENCE TEST 1 60 questions Time limit: 50 minutes1. To be isotopes, two atoms of the same element must have a differentnumber of (A) neutrons. (B) protons. (C) electrons. (D) quarks. 2. Depending on its environment, a substance that can act as either anacid or a base is described as (A) amphoteric. (B) an isomer. (C) hydrolytic. (D) a polymer. 3. A certain substance is not broken down in a chemical reaction. Thesubstance is most likely (A) a compound. (B) an aqueous solution. (C) an element. (D) a heterogeneous mixture. 4. A hydrogen ion concentration of 1 107 M in a solution is considered (A) basic. (B) alkali. (C) acidic. (D) neutral. 5. The radioactive isotope I131 has a half-life of 8 days. What fractionof a sample of I131 will remain after 24 days?(A) (B) (C) (D) 6. Which of the following particles/rays is not a type of radioactiveemanation? (A) alpha particle (B) beta particle (C) gamma ray (D) carbon-12 7. The strongest acid can be found in which of the following pH ranges? (A) 11.1 12 (B) 7.1