Question 1: Explain what an alloy is and how it differs from a pure metal.

Answer: An alloy is a mixture of two or more elements, at least one of which is a metal, created to improve properties like strength, durability, or corrosion resistance. Unlike pure metals, alloys have combined properties resulting from their constituent elements.

Question 1: Describe the mechanism by which alloying improves the strength of metals.

Answer: Alloying introduces different atoms into the metal's crystal lattice, which disrupts the regular arrangement of pure metal atoms. This interference makes it harder for the layers to slide past each other, increasing strength.

Question 2: List two common alloys and their primary uses.

Answer: Steel, used in construction and tools; Bronze, used in sculptures and musical instruments.

Question 1: An alloy contains 70 grams of iron and 30 grams of carbon. Calculate the percentage composition of each element in the alloy.

Answer: Iron: 70%; Carbon: 30%

Question 2: If a certain alloy contains 15% sulfur and 85% copper by mass, what is the mass of sulfur in a 200-gram sample?

Answer: 30 grams

Question 1: Design a simple experiment to test the corrosion resistance of different alloys. Include variables to control, variables to measure, and safety precautions.

Answer: Students should prepare samples of various alloys, expose them to a controlled corrosive environment such as saltwater, and measure the extent of corrosion over time. Variables to control include temperature, exposure time, and solution concentration. Variables to measure include weight loss or surface damage. Safety precautions include wearing gloves, eye protection, and working in a well-ventilated area.

Question 1: A sample of an alloy has a density of 8.4 g/cm³, which is higher than pure aluminum (2.7 g/cm³) but lower than pure copper (8.96 g/cm³). What can you infer about its composition?

Answer: The alloy likely contains a significant amount of copper with some aluminum, resulting in a density between that of pure aluminum and pure copper.

Question 2: A certain alloy is found to be 60% iron and 40% nickel by weight. Based on typical properties, what are some probable applications of this alloy?

Answer: Such an alloy is likely magnetic and corrosion-resistant, making it suitable for applications like jewelry, coins, or electrical components.

Question 1: Explain how alloying improves the mechanical properties of metals. Include at least two specific examples in your answer.

Answer: Alloying introduces different atoms into the metal's crystal structure, which can hinder the movement of dislocations, thereby increasing strength and hardness. For example, adding carbon to iron forms steel, which is stronger and harder than pure iron. Similarly, adding tin to copper produces bronze, which is more durable and corrosion-resistant.

Question 1: Discuss the importance of alloys in modern industry and provide two examples of alloys used in everyday life.

Answer: Alloys are crucial in industry because they enhance properties like strength, corrosion resistance, and appearance. Examples include stainless steel used in cutlery and construction, and brass used in musical instruments and fittings.

Question 2: Identify safety considerations to keep in mind when working with molten metals and alloys in industrial settings.

Answer: Safety considerations include wearing protective gloves and goggles, working in well-ventilated areas to avoid inhaling fumes, using proper tools to handle hot metals, and following protocols to prevent burns and fires.