Chemistry Trivia Questions and Answers
Chemistry Trivia Questions Part 1
1. In a solution, the substance that does the dissolving is the:
What is a Solvent.
A solvent is a liquid substance in which other substances can dissolve. Solvents are used to dissolve and dilute solutions. This makes it easier for substances to mix together. Solvent is also a substance that can dissolve another substance.
For example, water is a solvent for sugar. Liquids like water can dissolve more solid substances than gases like air can. That’s because liquids have small molecules that cling tightly together and surround the other substance in a little package called a molecule. When the package breaks open, the other substance dissolves into the water, which then becomes a solution of sugar dissolved in water. The sugar dissolves in the water but not vice versa due to polarity caused by partial charges on molecules. The charged regions are known as ions.
2. The scientific term for “water-hating” is:
Hydrophobic Explanation: Hydrophobic is a concept that has been defined by chemists for decades, but for most people it seems like a complicated subject.
The word ‘hydrophobic’ means ‘opposed to water’ as in hydrophobic is used to describe substances which are not soluble in water. A hydroxyl group is attached to the carbon atom making up the chain of an organic compound, and when this group attaches itself to a carbon atom which is within the structure of a hydrocarbon, it makes zigzag links with another hydrocarbon chain at the other side of it forming chains.
3. Solids such as salt and sugar dissolve more readily in:
Answer: Hot water.
Explanation: Solids can dissolve in either cold or hot water. However, more solids will dissolve in hot water than cold water. This is because a larger temperature difference between the solid and the liquid causes a larger energy barrier for the attraction between the molecules of the solid to overcome. The molecules of the solid attract each other by Coulomb’s law of electrical forces:
where F is force (N), q1 and q2 are charges on two particles separated by distance r (q1=+q2), k is Coulomb’s constant, e is charge on electron (-1.6×10 C) and r is distance between charges (m). Here we see that attractive forces increase with an increase in either charge or distance.
4. The type of plastic that is suitable for use as saucepan handles is:
Answer: Thermosetting plastics.
What is Thermosetting plastics?
Thermosetting plastic is a material that undergoes a chemical reaction following heating, which will make it unable to be remelted by room temperature. It will lose its flexibility and shape memory property. To color thermoset plastics, pigments are added during the manufacturing process or the resin can be pigment loaded to achieve color in-mold. The thermosetting polymers can be divided into three categories:
c) High-temperature cure systems
The three most well known thermoset compounds are Urea-formaldehyde, urethane and epoxy compounds.
Thermoset plastics, as the name suggests, are materials that set or harden with heat exposure. The thermosetting plastic compounds are mostly used in buildings and other construction projects where they can be molded into intricate shapes.
Advantages of using thermosetting plastics
This type of substance has several advantages when it comes to industrial design because of its strength and durability. It cannot be melted down again because it has been converted into a hardened substance. The thermoset is also non-flammable and quite affordable, about $600 per cubic meter. This means that it is very durable and lasts for a long period of time.
5. Whether a substance is opaque, translucent or transparent is a measure of the physical property of:
Answer: Its ability to transmit light.
A strong material through which light can pass will be translucent. Fluorescent lighting makes use of this property; the tubes themselves are made with a translucent or transparent glass that allows light to pass through them from a source of ultraviolet radiation. When sufficient voltage is applied across these tubes, they emit their own light without any other radiation source.
Decorative materials such as glass and porcelain are typically opaque, meaning they do not transmit light but appear clear because the individual particles that make up the material scatter all wavelengths equally.
6. A chemical reaction that takes in heat energy during the reaction is called:
Endothermic: Endothermic is a term used to describe a reaction that absorbs heat energy from the environment. The opposite of this is Exothermic. In chemical reactions, endothermic reactions absorb heat from the surroundings, so they are often slower than exothermic reactions that release heat. In food reactions, endothermic reactions require added heat to initiate and to proceed at a reasonable rate.
A chemical reaction which absorbs energy (heat) from its surroundings is classified as an endothermic reaction. The reverse of this is an exothermic reaction which releases energy into the surroundings and proceeds quite quickly than an endothermic reaction. Endotherms are generally slow and require heating before they start to react in the same way as exotherms.
7. In a decomposition type of chemical reaction, copper carbonate is heated and breaks down to form:
Answer: Copper oxide and carbon dioxide.
Copper oxide is a well-known semiconductor material. Its application as a semiconductor started in the 1970s with the development of high-quality transparent thin films of copper oxide by chemical vapour deposition. In 2008, it was used for solar cells to reach a conversion efficiency of 9.7 %, which is still an achievement in the field of solar cell research.
Within the scope of this paper, we want to give a short overview about the properties of copper oxide and some results of our more recent studies on the fabrication of single crystals and thin films.
Copper oxide is characterized by a direct bandgap energy of 1.5 eV, which is in the range for application in organic solar cells. The appropriate deposition method is not clear yet, but chemical vapour deposition seems to be useful. Moreover, copper oxide shows good optical transparency (inorganic) or even an increased absorption coefficient in certain wavelength ranges (organics), depending on the chosen substrate material. Copper oxide also has high thermal stability up to 1,000 °C.
Carbon dioxide is an even more well-known material. The CO2 molecule has a linear structure and is symmetric with respect to the carbon-oxygen double bond. The O···C distance is 146 pm and the C···O distance 122 pm. The bond angle is 109.5°. The molecule’s vibrational frequency has two peaks at 705 cm−1 and 1,364 cm−1.
Various mixed crystals of copper oxide with carbon dioxide can be synthesized by combustion of copper in an excess of dry, frozen CO2. A higher chemical reactivity of the metal atoms allows a direct reaction without any intermediate formation of oxides.
8. The name given to the chemical reaction that joins repeating units together to form polymers is:
Polymerisation Explanation: Polymerisation is the process of creating polymers from monomers. To produce a polymer from a monomer, a polymerisation reaction must occur where the functional groups on the two separate atoms bind together to form a covalent bond, resulting in a molecule with multiple repeating units.
The monomers are often organic compounds containing active hydrogen atoms (hydroxyl or carbonyl groups) and carbon-to-carbon double bonds on carbon rings. These are typically referred to as olefins (from the Latin name for oil) and cyclic olefins.
9. Vinegar, aspirin and vitamin C are examples of household:
What are Acids?
Acids are chemical substances that can be either solid or liquid in form and are the most common corrosive found in the environment, they can be found naturally in the body of humans and animals as well.
They have a sour taste and are commonly found occurring for example in carbonated drinks such as lemonade or cola, which contain citric acid.
But they’re also produced by the human body – acids makeup about 15% of blood, keeping it slightly alkaline,(acid-base balance) and making it more difficult for bacteria to multiply. If blood were too acidic it would kill us because many of our proteins would disintegrate, resulting in death.
10. Limewater has the chemical name of:
Answer: Calcium hydroxide.
Calcium hydroxide (Ca(OH)2), commonly known as slaked lime, is a chemical compound. Its basicity (pKa = 10.3) is similar to that of ammonia and for this reason it is often used in soil and wastewater treatments.
Chemistry Trivia Questions Part 2
11. The smallest hydrocarbon is:
What is methane?
Methane is a colourless, odourless, non-poisonous gas. It is the main component of natural gas, which is found in underground deposits and used as a source of fuel. Methane can also occur naturally in other places, such as wetlands; it can be released by chemical reactions that occur in the absence of oxygen or sunlight.
12. A substance which changes different colours in acids and bases is called:
Answer: An indicator.
An indicator is a substance that changes its colour according to the acidity of a solution.
Acid turns it red, alkaline turns it blue or green, and neutral turns it yellow.
indicators can be used to measure acidity in solutions because they change properties as acids or bases are added to them.
13. The mineral from which aluminium is extracted is:
What is Bauxite?
Bauxite is a sedimentary rock made up mainly of the mineral, aluminium oxide (Al2O3). The name bauxite is derived from the name of the village where it was first discovered in 1821, Baux, in Provence, France. It is now recognised that bauxite comes principally from two geologic deposits: lateritic and karst deposits.
Karst deposits are formed in tropical regions when soluble rocks such as limestone are weathered by rain dripping through cracks in the rock. On a very large scale, the chemical weathering results in acid forming as rainwater attacks the rocks.
14. The refining of a pure metal in a blast furnace is called:
Smelting is the process of extracting metals from their ores. Smelting uses heat and a chemical reducing agent to decompose the ore, driving off other elements as gasses or slag and leaving just the metal behind.
15. The process whereby catalysts are added to certain hydrocarbons in order to break them into smaller hydrocarbons suitable for petrol and plastics is called:
Cracking is a chemical process that consists of breaking complex molecules down into simpler ones.
In the petroleum refining industry, cracking is done to convert heavy hydrocarbons (like gasoline, diesel and jet fuel) into lighter ones (like kerosene, which burns more cleanly than other fuels).
Cracking can occur in the chemical processes involved in burning fossil fuels or in coal production. In this case, cracking releases smaller hydrocarbon molecules containing more hydrogen atoms from larger ones – usually from long-chain hydrocarbons.
The result of cracking is that each molecule of fuel contains fewer carbon atoms and leaves behind gaseous carbon dioxide (CO2). Less CO2 means less greenhouse gas and less global warming.
16. Examples of natural polymers are:
Answer: Proteins and silk.
Natural polymers are biopolymers that are based on monomer units that contain a number of carbon atoms in the range of hundreds to thousands. Natural polymers are synthesized with high order structures and therefore they posses unique properties when compared to other synthetic polymers like synthetic plastics and rubber. Some examples of natural polymers include proteins, nucleic acids, carbohydrates, lipids.
17. What is the name of the polymerisation process where water is produced when the monomers join to make a polymer?
Answer: Condensation polymerisation.
Condensation polymerisation is a type of polymerisation. It involves the reaction of two or more monomers with the elimination of water or other small molecules.
Polymerisation reaction is a process in which small molecules are bonded together to produce larger molecules.
An example of condensation polymerisation is the process by which starch is produced from smaller sugar molecules. In this case, the individual sugar units are linked together chemically and form long chains that makeup starch. Another example of condensation polymerisation occurs in cellulose production, where glucose units link to each other and form large chains.
18. Soaps were originally made from:
Answer: animal fats and vegetable oils.
Today, soaps are made from mineral oils that are made by the crude oil distillation process.
Pure fats are not soaps because fats dissolve in oil, solvent and water but not in water alone. Soap is a mixture of different substances.
Pure animal fats like tallow are changed chemically and become different substances called glycerides when they undergo saponification – the addition of oxygen to their molecules by an alkali. An alkali is a base such as lye (or sodium hydroxide or potassium hydroxide) or some other compound that releases hydroxide ions (OH-) when it is dissolved in water.
Because fats (like butter or tallow) have a low reaction temperature, they are heated with an alkali until they become a soap.
Vegetable oils like olive oil are not changed chemically before they become soap. They simply react by saponification with a natural alkali – in this case, an alkali within the olive oil itself.
Then the fatty acid salt is neutralized with an acid such as sulfuric acid to make it milder. Sodium hydroxide or potassium hydroxide will saponify fats but it has to be kept in water at all times otherwise it will burn or explode! Sulfuric acid is much stronger and can be used alone to make soaps.
19. Hard water contains a lot of calcium and:
Answer: magnesium salts.
The salt in hard water has a positive ion charge. Because most substances dissolve better in water when the water is neutralized, the negative ions in tap water are attracted to the positive ion charge of the calcium and magnesium salts.
The metals dissolve because the negative ions are attracted to them.
20. When phosphates from cleaning products reach our waterways, they encourage the rapid growth of algae. This in turn extracts too much oxygen from the water and fish suffocate. This harmful process is:
Eutrophication is the process of a lake becoming nutrient-rich.
When this happens, algae and plants grow and multiply very quickly, sometimes causing problems for humans. It can also lower oxygen levels in the water, making it unsuitable for fish to live there.
What causes eutrophication?
There are two main types of eutrophication: ‘point source’ and ‘non-point source’. This means different things… The first type is when nutrients enter a water body from a single place (such as sewage or animals on farms). The second type is when they come from many different places (for example from soil erosion during heavy rain).