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Which compounds are electrolytes?*
Which substance is an electrolyte?*
Which two compounds are electrolytes?*
The electrical conductivity of an aqueous solution depends on the concentration of which particles in the solution?*
Why is potassium nitrate classified as an electrolyte?*
Which statement describes an electrolyte?*
Which compound is an electrolyte?*
Which compounds are classified as electrolytes?*
Base your answers to questions 10 on the information below.
Ammonium chloride is dissolved in water to form a 0.10 M NH4Cl(aq) solution. This dissolving process is represented by the equation below.
Explain, in terms of ions, why a 10.0-milliliter sample of 0.30 M NH4Cl(aq) is a better conductor of electricity than a 10.0-milliliter sample of the 0.10 M NH4Cl(aq).*
Base your answers to questions 11 on the information below and on your knowledge of chemistry.
A laboratory technician is given the table below and a sample of one of the three substances listed in the table. The technician makes an aqueous solution with a portion of the sample. When a conductivity tester is lowered into the solution, the lightbulb on the tester glows brightly. Another portion of the sample is placed in a heat-resistant container that is placed in an oven at 450.°C. The sample melts.
Explain, in terms of ions, why an aqueous solution of potassium chromate conducts an electric current.*
Base your answers to questions 12 on the information below.
Calcium reacts with water. This reaction is represented by the balanced equation below. The aqueous product of this reaction can be heated to evaporate the water, leaving a white solid, Ca(OH)2(s).
Ca(s) + 2H2O(ℓ) → Ca(OH)2(aq) + H2(g)
Compare the electrical conductivity of the aqueous product in the reaction to the electrical conductivity of the white solid that remains after the water is evaporated from the solution.*
Base your answers to questions 13 on the information below and on your knowledge of chemistry.
A small digital clock can be powered by a battery made from two potatoes and some household materials. The “potato clock” battery consists of two cells connected in a way to produce enough electricity to allow the clock to operate. In each cell, zinc atoms react to form zinc ions. Hydrogen ions from phosphoric acid in the potatoes react to form hydrogen gas. The labeled diagram and balanced ionic equation below show the reaction, the materials, and connections necessary to make a “potato clock” battery.
Explain why phosphoric acid is needed for the battery to operate.*
Base your answers to questions 14 on the information below and on your knowledge of chemistry.
Vinegar is a commercial form of acetic acid, HC2H3O2(aq). One sample of vinegar has a pH value of 2.4.
Explain, in terms of particles, why HC2H3O2(aq) can conduct an electric current.*
Base your answers to questions 15 on the information below and on your knowledge of chemistry.
In a laboratory investigation, an HCl(aq) solution with a pH value of 2 is used to determine the molarity of a KOH(aq) solution. A 7.5-milliliter sample of the KOH(aq) is exactly neutralized by 15.0 milliliters of the 0.010 M HCl(aq). During this laboratory activity, appropriate safety equipment is used and safety procedures are followed.
Explain, in terms of aqueous ions, why 15.0 mL of a 1.0 M HCl(aq) solution is a better conductor of electricity than 15.0 mL of a 0.010 M HCl(aq) solution.*
