10. producing sodium chloride (table salt) using the reaction in figure 1 on page 192 is impractical and…

10. producing sodium chloride (table salt) using the reaction in figure 1 on page 192 is impractical and expensive. sodium chloride can be extracted from seawater. how could this be done using a common renewable energy source? 11. (a) compare the electrical conductivity of pure water, tap water, and seawater. (b) why is there a difference? 12. a penny and a dime inserted into a pickle and connected in

10. producing sodium chloride (table salt) using the reaction in figure 1 on page 192 is impractical and expensive. sodium chloride can be extracted from seawater. how could this be done using a common renewable energy source? 11. (a) compare the electrical conductivity of pure water, tap water, and seawater. (b) why is there a difference? 12. a penny and a dime inserted into a pickle and connected in

Answer

  1. Sodium chloride can be extracted from seawater through processes like evaporation - crystallization. Seawater contains dissolved salts including sodium chloride. By evaporating the water (usually using solar energy which is a common renewable energy source), the salt concentration increases until the sodium chloride crystallizes out. However, it is impractical and expensive mainly because large - scale evaporation requires a lot of space and energy. Also, purifying the extracted salt to a high - quality table salt standard involves additional processing steps which add to the cost.
  2. a. Pure water has very low electrical conductivity because it has very few ions. Tap water contains dissolved minerals such as calcium, magnesium, and other salts which dissociate into ions in water, increasing its conductivity. Seawater has a much higher electrical conductivity than tap water. It contains a large amount of dissolved salts (e.g., sodium chloride, magnesium chloride etc.) which dissociate into a high concentration of ions in the solution, allowing for better flow of electric current.
  3. When a penny and a dime are inserted into a pickle and connected, there is a difference likely due to the different metals in the coins. A penny is mainly made of copper (with some zinc), and a dime is made of a copper - nickel alloy. These different metals have different electrochemical properties. In the acidic environment of the pickle (which acts as an electrolyte), a redox reaction can occur at the metal - electrolyte interfaces. The different standard reduction potentials of the metals in the coins lead to a potential difference and thus a flow of electrons (a current), resulting in a measurable difference.