SELAMAT DATANG Kuiz Sains Tambahan Tingkatan 5 Bab 2 Set 1
Penerokaan Unsur Dalam Alam (English)
KUIZ INI MENGANDUNGI 10 SOALAN
1. A student adds sodium hydroxide solution to an unknown salt solution, forming a white precipitate. When excess sodium hydroxide is added, the precipitate dissolves to form a colorless solution. Based on the provided flowcharts, which cation could be present?
2. A student heats a white crystalline salt in a test tube. The residue is yellow when hot and turns white upon cooling. A gas is also produced that turns limewater cloudy. What is the most likely identity of the salt?
3. During the preparation of copper(II) chloride from copper(II) oxide and hydrochloric acid, why is the copper(II) oxide powder added in excess?
4. In the reaction MgCO3 + 2HCl→MgCl2 + CO2 + H2O, what is the mole ratio of magnesium carbonate (MgCO3) to hydrochloric acid (HCl) that is required for a complete reaction?
5. A student performs a flame test on a salt and observes no distinct color. Then, the student adds sodium hydroxide solution to an aqueous solution of the salt and gently warms it. A gas is produced that turns damp red litmus paper blue. Which cation is present?
6. Which of the following methods is most suitable for preparing a pure, dry sample of the insoluble salt lead(II) iodide (PbI2)?
7. The substance known as 'Plaster of Paris' is used in medicine to create casts for broken bones. According to the textbook, what is the chemical name for this salt?
8. To test for the presence of chloride ions (Cl−) in a solution, which two reagents are typically added in sequence?
9. When solid zinc carbonate (ZnCO3) is heated strongly, it undergoes thermal decomposition. What are the expected products?
10. What is the most suitable method for preparing an insoluble salt like lead(II) sulfate (PbSO4)?
