1. Describe a hydrocarbon.

Question

2. How many bonds can Carbon make? This is what makes it unique.
3. How is it that glucose can be linked together to form both cellulose and starch?
4. What is the relationship between the nutrients you eat and your body’s biochemistry? (In other word, how is it true that “You are what you eat.”)
5. What does the law of conservation of matter say?
6. What is cellular respiration?
7. What role does the mitochondria play in a cell? What organ plays this role in the body?
8. How can you tell the difference between an endothermic and exothermic reaction?
9. What is the difference between reactants and products?
10. How can the rate of a reaction be measured using products or reactants?
11. Why does ice float?

Answer 1

Here are answers to your questions:

1. Describe a hydrocarbon. A hydrocarbon is a chemical compound that consists exclusively of hydrogen and carbon atoms. They can be classified into different categories based on their structure and bonding; for example, alkanes (single bonds), alkenes (at least one double bond), and alkynes (at least one triple bond). Hydrocarbons are the fundamental components of fossil fuels, like coal, oil, and natural gas, and they serve as the backbone for many organic molecules.

2. How many bonds can Carbon make? Carbon can form four covalent bonds with other atoms. This tetravalency is due to carbon having four electrons in its outer shell and needing four more to achieve a stable electron configuration (octet rule). This unique ability allows carbon to form complex and diverse organic molecules, making it a fundamental element of life.

3. How is it that glucose can be linked together to form both cellulose and starch? Glucose molecules can be linked together in different configurations to form various polysaccharides based on the type of glycosidic bonds formed. In starch, glucose units are linked primarily by α-1,4 glycosidic bonds, resulting in a branched structure that is energy-storing. In cellulose, glucose units are linked by β-1,4 glycosidic bonds, leading to a linear structure that provides strength and rigidity in plant cell walls. The arrangement and type of bond formed determine the function and properties of these polysaccharides.

4. What is the relationship between the nutrients you eat and your body’s biochemistry? The nutrients you consume—carbohydrates, proteins, fats, vitamins, and minerals—are essential for various biochemical processes in the body. For example, carbohydrates are broken down into glucose, which provides energy, while proteins are broken down into amino acids, which are used for building and repairing tissues. The foods you eat supply the building blocks and energy necessary for your body to function properly, connecting the saying "You are what you eat" to the fact that your body's structure and function depend on your dietary choices.

5. What does the law of conservation of matter say? The law of conservation of matter states that matter cannot be created or destroyed in a closed system; it can only be transformed from one form to another. This principle implies that the mass of reactants in a chemical reaction must equal the mass of the products, indicating that all atoms present before the reaction are still present after the reaction, just rearranged.

6. What is cellular respiration? Cellular respiration is a metabolic process that occurs in cells to convert biochemical energy from organic molecules, such as glucose, into adenosine triphosphate (ATP), the energy currency of the cell. This process involves a series of chemical reactions and typically takes place in the mitochondria, where oxygen is used to break down glucose, producing carbon dioxide and water as byproducts.

7. What role does the mitochondria play in a cell? What organ plays this role in the body? Mitochondria are known as the "powerhouses" of the cell because they are responsible for producing ATP through cellular respiration. They convert energy stored in nutrients into a usable form of energy for the cell. In terms of organs, the heart can be thought of as playing a similar role in the body, as it pumps blood (which delivers nutrients and oxygen) throughout the body, supplying cells with the necessary materials for energy production.

8. How can you tell the difference between an endothermic and exothermic reaction? The primary difference between an endothermic and exothermic reaction lies in the direction of energy flow. An exothermic reaction releases energy, usually in the form of heat, to the surroundings, which may cause a rise in temperature. In contrast, an endothermic reaction absorbs energy from the surroundings, which can lead to a decrease in temperature. This can often be observed by measuring temperature changes during the reaction.

9. What is the difference between reactants and products? In a chemical reaction, reactants are the starting substances that undergo a transformation, while products are the new substances formed as a result of the reaction. The reactants are present before the reaction takes place, and the products are produced as the reaction reaches completion.

10. How can the rate of a reaction be measured using products or reactants? The rate of a chemical reaction can be measured by observing the change in concentration of reactants over time or the change in concentration of products over time. For example, the decrease in concentration of a reactant can indicate the speed at which it is being consumed, while the increase in concentration of a product can reflect how quickly the reaction is proceeding.

11. Why does ice float? Ice floats on water because it is less dense than liquid water. When water freezes, its molecules form a crystalline structure that is more spacious than in the liquid state, resulting in lower density. This unique property of water is essential for aquatic life, as it allows ice to act as an insulating layer on top of water bodies, preventing them from freezing solid and protecting the organisms below.