Q7. Ventricles contracting means 'heart pumping'. So the valve between ventricles and arteries should open to enable blood outflow. On the other hand, the valve between atria and ventricle should close to stop blood backflow. So B.
Q11. Mitosis starts with a diploid cell and produces 2 diploid cells. Meiosis starts with a diploid cell and produces 4 haploid cells. So C.
Q18. Aqueous copper sulfate is water + copper sulfate. So when electrolyzed, the electrolyte splits to hydrogen, hydroxide, copper, and sulfate ions.
In anode, anions are attracted (hydroxide and sulfate). The trend for electrolysis is halogen>oxygen/hydroxide>other ions, so oxygen is produced from the electrolysis of hydroxide.
In cathode, cations are attracted (copper and hydrogen). The trend is less reactive ion being electrolyzed. Copper is less reactive than hydrogen, so copper is electrolyzed. So C.
Q19. Chlorine becomes chloride ion (anion) and Iodide ion (anion) becomes iodine after the reaction. During this reaction, chlorine gains electron (becomes reduced) and iodide ion loses electron (becomes oxidized). Hence, chlorine is an oxidizing agent, which oxidizes iodide ions. So A.
Q33. The definition for waves: Waves transfer energy but not matter. Matter only oscillates. So it's C.
Hi, thank you for your question.
Q7. Ventricles contracting means 'heart pumping'. So the valve between ventricles and arteries should open to enable blood outflow. On the other hand, the valve between atria and ventricle should close to stop blood backflow. So B.
Q11. Mitosis starts with a diploid cell and produces 2 diploid cells. Meiosis starts with a diploid cell and produces 4 haploid cells. So C.
Q18. Aqueous copper sulfate is water + copper sulfate. So when electrolyzed, the electrolyte splits to hydrogen, hydroxide, copper, and sulfate ions.
In anode, anions are attracted (hydroxide and sulfate). The trend for electrolysis is halogen>oxygen/hydroxide>other ions, so oxygen is produced from the electrolysis of hydroxide.
In cathode, cations are attracted (copper and hydrogen). The trend is less reactive ion being electrolyzed. Copper is less reactive than hydrogen, so copper is electrolyzed. So C.
Q19. Chlorine becomes chloride ion (anion) and Iodide ion (anion) becomes iodine after the reaction. During this reaction, chlorine gains electron (becomes reduced) and iodide ion loses electron (becomes oxidized). Hence, chlorine is an oxidizing agent, which oxidizes iodide ions. So A.
Q33. The definition for waves: Waves transfer energy but not matter. Matter only oscillates. So it's C.