Transition Metals And Their Uses Quiz

Explanation
Iron is the catalyst in the Haber process. The Haber process is a chemical reaction used to produce ammonia, which is an important compound in the production of fertilizers and other chemicals. The catalyst, in this case, iron, helps to speed up the reaction without being consumed itself. Iron acts as a surface for the reactant molecules to bind to, allowing them to come together and react more easily. This increases the rate of ammonia production and makes the process more efficient.

Explanation
Nickel is used to harden oils when making margarine. This is because nickel acts as a catalyst in the hydrogenation process, which is used to convert liquid vegetable oils into solid fats. Hydrogenation involves adding hydrogen atoms to unsaturated fatty acids in the oil, making them saturated and solid at room temperature. Nickel helps to speed up this process and improve the texture and consistency of the margarine.

Explanation
Gold is used in dental work because it is strong and fairly unreactive. Gold is a highly durable and resilient metal, making it suitable for use in dental restorations that need to withstand the forces of chewing and biting. Additionally, gold is fairly unreactive, meaning it does not easily corrode or react with other substances in the mouth, ensuring its longevity and stability in dental applications.

Explanation
Copper compounds are blue because they often contain copper ions that absorb light in the red and green regions of the electromagnetic spectrum, while reflecting or transmitting blue light. This selective absorption of light results in the blue color observed in many copper compounds.

Explanation
A precipitate is a solid substance that forms when two solutions react with each other. It is formed when the reaction causes the formation of insoluble particles, which then settle out of the solution. Therefore, the correct answer is solid.

Explanation
The transition elements are found in the middle of the periodic table, between groups 2 and 13. They are characterized by their ability to form multiple oxidation states and their partially filled d orbitals. Option B states "nowhere," which implies that the transition elements cannot be found on the table, which is incorrect.

Explanation
Copper is the most used transition metal because it is strong and a good conductor of electricity. This makes it ideal for various applications, especially in electrical wiring and electronic devices. Its strength ensures durability, while its excellent conductivity allows for efficient flow of electricity. Additionally, copper is relatively inexpensive compared to other transition metals, making it a cost-effective choice for many industries.

Explanation
The correct symbol for Gold is Au, derived from its Latin name "aurum." This symbol is used internationally to represent Gold in various contexts such as chemical equations, scientific research, and financial markets.

Explanation
Transition metal compounds react with sodium hydroxide to form precipitates. Sodium hydroxide is a strong base that can react with transition metal ions to form insoluble metal hydroxides. This reaction is commonly used in qualitative analysis to identify transition metal ions in a solution. When sodium hydroxide is added to a solution of a transition metal compound, a colored precipitate is formed, indicating the presence of a specific transition metal ion.

Explanation
When metal carbonates decompose thermally, they break down into their respective metal oxide and carbon dioxide. Therefore, the gas given off during this process is carbon dioxide.