Question 3: Electrochemical Coll (15 points) A high school girl was getting ready for a big date but discovered with horror that her silver neckli
was tarnished. Having just studied about redox reactions and electrochemical cells in chemistry
class, she grabbed some aluminum foil, put it in a dish, and placed her necklace on top of the foi
Then she added some baking soda, a little salt, and hot water. Within a few minutes, her necklace
was bright and shiny again
The formula for silver tarnish is AgzS. Use the balanced equation to answer the following question
3A52S + 2Al(s) → A12S3 + 6Ag(s)
a. What makes this an oxidation-reduction reaction? (1 point)
b. Write the half-reactions showing the oxidation and reduction reactions. Identify which is the
oxidation reaction and which is the reduction reaction (3 points)
c. What is oxidized in the reaction? What is reduced? (2 points)

uranium-238 i believe is your answer

out of these options:

ability to burn paper

pure sodium reacting violently with water

the boiling point of water

helium does not tend to react with anything

i would say this is a physical property:

helium does not tend to react with anything

why? :

i said helium does not tend to react with anything because well, it reacts to ! but ability to burn paper, pure sodium reacting violently with water, & the boiling point of water are chemical or

physical properties: the properties of a substance that can be observed without changing the chemical makeup of the substance

chemical properties: properties of a substance relating to the chemical nature and reactivity of the substance

the number of valence electrons for each molecule or ion is shown beneath the structure. remember hydrogen will not have more than two electrons. this hydrogen is part of a covalent bond (sharing two electrons). a double bond here would cause hydrogen to share four electrons with phosphorus.