If the standard reduction potential of a half-cell is positive, the reduction reaction is spontaneous when paired with a hydrogen electrode
<u>Explanation:</u>
- The relative standard reduction potential of the half-cell in which reduction occurs; more positive than the other half-cell.
- If the standard reduction potential of a half-cell is positive, the reduction reaction is spontaneous when paired with a hydrogen electrode.
- The reduction is a chemical process in which electrons are added to an atom or an ion; it always occurs accompanied by oxidation of the reducing agent.
- The reduction to happen the electrons gained by the material that is being decreased must be transported from the atoms of ions of a different material.
Answer:
1.08 g/mL
Explanation:
Density=Mass/Volume therefore you would do the mass which is 7.481 g divided by the volume which is 6.9 mL and get 1.08 g/mL since you combine the two labels!
Answer:
Lithium selenide Lithium selenide (Li2Se) 12136-60-6 Dilithium selenide lithium selenidolithium
Molecular Weight 92.9 g/mol
Dates Modify 2020-11-15 Create 2005-08-08
As a general rule of thumb molecules where metals interact with non-metals tend to form ionic bonds (because they form oppositely-charged ions), while molecules where non-metals interact with non-metals tend to form covalent bonds (because they share electrons to fill valence shells). Some of the options listed refer to large polymers of more basic units - if you can identify the basic units, you can get a sense of the kinds of bonds you're dealing with.
Starch is a polymer of glucose. Glucose is an organic molecule made of C, H, and O (all non-metals). It contains COVALENT bonds.
Graphite is a carbon polymer (sort of). Carbon is a non-metal. It contains COVALENT bonds.
Paraffin wax is a mixture of long-chain hydrocarbons (lots of carbons stuck together with some hydrogens stuck around the edges). Non-metals again. COVALENT.
Copper nitrate is a metal (copper) and a non-metal (the polyatomic ion nitrate, NO3-). Therefore, copper nitrate as a whole is IONIC (be careful though - the N and O within the nitrate ion are both non-metals and so are bonded covalently, but they ultimately form an ion that is capable of forming ionic bonds with metals).
Iron oxide is a general term for some combination of iron (a metal) and oxygen (a non-metal). Regardless of the specific combination, the interaction is IONIC.
Sucrose is formed when glucose interacts with another sugar, fructose. Again, only C, H, and O are involved, so the molecule is COVALENT.
Calcium carbonate is similar to the copper nitrate situation - you have a metal (calcium) and a non-metal (carbonate) interacting though an IONIC bond. As with nitrate, carbonate (CO3[2-]) is itself a polyatomic anion containing covalent bonds between the C and O's, but forms ionic bonds because it is ultimately an ion.
Happy to clarify anything if need be!