In 1916, scientists working in laboratories relied heavily on glassblowing skills to create specialized equipment. Which of the following glass types was considered the most expensive, but also offered the best resistance to cracking and sudden temperature changes?
- Soda Glass
- Lead Glass
- Hard Glass
- Vitreous Silica
Correct Answer: Lead Glass
Correct Answer Explanation: Lead glass, also known as English glass, was prized for its durability and resistance to thermal shock, making it a suitable choice for various scientific applications.
What is the name given to the process where glass or silica loses transparency and develops a crystalline structure, often caused by contamination or improper heating?
- Annealing
- Devitrification
- Oxidization
- Reduction
Correct Answer: Devitrification
Correct Answer Explanation: Devitrification is a phenomenon that can occur when glass or silica is heated improperly or contaminated, causing it to lose its transparency and form crystalline structures.
When working with silica, a special type of flame is needed to achieve the high temperatures required for softening and shaping the material. Which of the following describes this flame?
- Pointed Flame
- Brush Flame
- Oxy-Gas Flame
- Candle Flame
Correct Answer: Oxy-Gas Flame
Correct Answer Explanation: An oxy-gas flame, produced by burning oxygen and a fuel gas like hydrogen, generates extremely high temperatures needed to work with vitreous silica, which has a very high melting point.
Vitreous silica, a highly pure form of silica, is prized for its unique properties. Which of the following is NOT a characteristic of vitreous silica?
- High melting point
- Low thermal expansion
- High thermal conductivity
- Resistance to thermal shock
Correct Answer: High thermal conductivity
Correct Answer Explanation: Vitreous silica is actually a very poor conductor of heat, making it an excellent insulator. This property is advantageous in various applications, including high-temperature experiments and electrical insulation.
In 1916, a particular type of silica was preferred for making vitreous silica apparatus due to its purity and ease of preparation. What was this type of silica known as?
- Sand
- Quartz
- Brazil Pebble
- Chalcedony
Correct Answer: Brazil Pebble
Correct Answer Explanation: Brazil Pebble, a variety of native silica, was preferred for its purity and ease of preparation for making vitreous silica apparatus. It was considered more manageable than other forms of quartz for glassblowing purposes.
The book “The Methods of Glass Blowing and of Working Silica in the Oxy-Gas Flame” was written in 1916 by W.A. Shenstone, F.R.S. What does “F.R.S.” stand for?
- Fellow of the Royal Society
- Fellow of the Royal Science
- Foundation of Royal Sciences
- Faculty of Royal Scientists
Correct Answer: Fellow of the Royal Society
Correct Answer Explanation: “F.R.S.” stands for “Fellow of the Royal Society,” a prestigious scientific society in the United Kingdom. This designation signifies that W.A. Shenstone was a recognized and respected member of the scientific community.
What is the name given to the process of slowly cooling hot glass or silica to relieve internal stresses and prevent cracking?
- Devitrification
- Reduction
- Annealing
- Oxidization
Correct Answer: Annealing
Correct Answer Explanation: Annealing is a crucial step in glassblowing and silica working, where hot materials are gradually cooled to prevent the formation of internal stresses that could lead to cracking during the cooling process.
Why was it considered important for scientists in 1916 to acquire glassblowing skills?
- Glassblowing was a highly sought-after profession.
- It allowed them to create custom-made equipment for their specific research needs.
- Glassblowing was a fun and engaging hobby.
- It was a way to impress colleagues with their craftsmanship.
Correct Answer: It allowed them to create custom-made equipment for their specific research needs.
Correct Answer Explanation: In the early 20th century, laboratory equipment was not as readily available as it is today. Glassblowing skills enabled scientists to create custom-made tools tailored to their particular research projects, saving costs and facilitating their work.
When working with lead glass, it was essential to ensure that the lead on the surface of the glass was re-oxidized. Which type of flame was used for this process?
- Pointed Flame
- Brush Flame
- Oxy-Gas Flame
- Candle Flame
Correct Answer: Pointed Flame
Correct Answer Explanation: A pointed flame, with its focused and intense heat, was ideal for re-oxidizing reduced lead on the surface of lead glass. This process helped maintain the glass’s workability and prevent discoloration.
What is the primary function of a blowpipe in glassblowing?
- To blow air into the glass to create bubbles.
- To melt the glass into a liquid form.
- To direct a flame for heating and shaping the glass.
- To cut the glass into desired shapes.
Correct Answer: To direct a flame for heating and shaping the glass.
Correct Answer Explanation: A blowpipe directs a flame, typically fueled by a mixture of gas and air, to heat and soften the glass, allowing it to be manipulated and shaped into various forms.
Which type of flame is best suited for heating larger areas of glass during glassblowing?
- Pointed Flame
- Brush Flame
- Oxy-Gas Flame
- Candle Flame
Correct Answer: Brush Flame
Correct Answer Explanation: A brush flame, with its wider and less concentrated heat, is ideal for heating larger areas of glass evenly. This type of flame is especially useful for working with thicker glass sections.
What is the term used for a connection between different pieces of apparatus made using mercury?
- Mercury Joint
- Mercury Seal
- Mercury Trap
- Mercury Valve
Correct Answer: Mercury Joint
Correct Answer Explanation: Mercury joints were commonly used in 1916 laboratories to create air-tight connections between different parts of apparatus. The mercury’s fluidity and resistance to air allow for secure sealing while also providing flexibility for disassembling the setup.
When working with glass or silica, what is the purpose of using a brick or a block of wood during heating?
- To provide support for the glass.
- To check for radiation and prevent uneven cooling.
- To create a more intense flame.
- To help cut the glass.
Correct Answer: To check for radiation and prevent uneven cooling.
Correct Answer Explanation: Placing a brick or a block of wood near the glass being heated helps monitor the radiation emitted and prevents uneven cooling, which could cause stress and cracking in the glass.
The author of the book emphasizes the importance of cleanliness when working with silica. Why is this so important?
- Cleanliness makes the work easier and faster.
- Cleanliness prevents the formation of unsightly marks on the silica.
- Even small amounts of contamination can affect the material’s properties and lead to devitrification.
- Cleanliness is a safety requirement in the laboratory.
Correct Answer: Even small amounts of contamination can affect the material’s properties and lead to devitrification.
Correct Answer Explanation: Contamination from impurities like dust or chemical residues can significantly alter the properties of silica, leading to devitrification, where the material loses its transparency and forms crystalline structures.
What was one of the key reasons scientists in 1916 were interested in working with vitreous silica compared to traditional glass?
- Vitreous silica was cheaper and easier to obtain.
- Vitreous silica was more aesthetically pleasing.
- Vitreous silica had a higher melting point and was more resistant to thermal shock.
- Vitreous silica was easier to work with using the blowpipe.
Correct Answer: Vitreous silica had a higher melting point and was more resistant to thermal shock.
Correct Answer Explanation: Vitreous silica’s high melting point and remarkable resistance to thermal shock made it ideal for high-temperature experiments and handling, expanding the possibilities of scientific research.
What is the approximate mean coefficient of expansion of vitreous silica?
- 0.00000059
- 0.0000059
- 0.000059
- 0.00059
Correct Answer: 0.00000059
Correct Answer Explanation: The mean coefficient of expansion of vitreous silica is remarkably low, about one-seventeenth that of platinum. This low expansion makes it highly stable at high temperatures, crucial for scientific applications.
The book describes a method for making a non-splintering variety of silica using Brazil Pebble. What is this process called?
- Annealing
- Devitrification
- Tempering
- Reduction
Correct Answer: Tempering
Correct Answer Explanation: Tempering is a process used to create a more durable and less splintering silica. In this case, Brazil Pebble chips are heated and then plunged into cold water, creating internal stresses that make the silica stronger and less likely to shatter.
What type of apparatus is used for the electrolysis of water, as described in the book?
- Hofman’s Apparatus
- Bunsen Burner
- Vacuum Tube
- Mercury Joint
Correct Answer: Hofman’s Apparatus
Correct Answer Explanation: Hofman’s Apparatus is a device specifically designed for the electrolysis of water, where an electric current is used to decompose water into hydrogen and oxygen gases. This apparatus is often built using glassblowing techniques, demonstrating the practical applications of these skills.
The book mentions a particular type of tap used for controlling gas flow and maintaining vacuum in experiments. What is this tap called?
- Vacuum Tap
- Mercury Tap
- Air Tap
- Pressure Tap
Correct Answer: Vacuum Tap
Correct Answer Explanation: Vacuum taps, like Cetti’s and Gimmingham’s, are specialized valves used to control the flow of gases and maintain vacuum in laboratory experiments. They are essential for various applications, including the manipulation of gases and the creation of controlled environments.
What is the term used to describe a device that prevents air bubbles from entering evacuated spaces during mercury flow?
- Air Trap
- Mercury Trap
- Vacuum Trap
- Pressure Trap
Correct Answer: Air Trap
Correct Answer Explanation: Air traps are designed to prevent air bubbles from contaminating evacuated spaces during mercury flow in experiments. They act as barriers, preventing air from entering the system and ensuring that the desired vacuum is maintained.
What is the primary goal of calibrating a burette?
- To ensure the burette is clean.
- To determine the exact volume delivered at each division.
- To check if the burette is leak-proof.
- To create a uniform flow of liquid from the burette.
Correct Answer: To determine the exact volume delivered at each division.
Correct Answer Explanation: Calibrating a burette involves filling it with water, drawing off portions, and weighing them to determine the exact volume delivered at each division. This process is essential for accurate measurements in titrations and other chemical experiments.
What was the significance of the book “The Methods of Glass Blowing and of Working Silica in the Oxy-Gas Flame” in the context of scientific research in 1916?
- It provided detailed instructions for creating custom laboratory equipment, empowering scientists to tailor their tools to their specific needs.
- It highlighted the growing importance of glassblowing skills in scientific research, as custom-made equipment became increasingly essential.
- It introduced new techniques for working with vitreous silica, a material with unique properties that opened up new possibilities for experimentation.
- It reflected the changing landscape of scientific research, where advancements in materials and techniques were transforming the possibilities of experimentation.
Correct Answer: All of the above.
Correct Answer Explanation: The book was significant for all these reasons. It provided practical guidance for glassblowing and silica working, highlighting the growing importance of these skills in scientific research. It introduced new techniques for working with vitreous silica, a material with unique properties that expanded the possibilities of experimentation. It reflected the changing landscape of scientific research, where advancements in materials and techniques were transforming the possibilities of experimentation.