Among the choices provide above the <span>redox reactions do you expect to occur spontaneously in the forward direction is the below:
</span><span>Fe2+(aq) + Zn(s) -> Fe(s) + Zn2+(aq)
</span><span> Al(s) + 3Ag+(aq) -> Al3+(aq) + 3Ag(s)
</span>
<span>Those reactions will proceed when the metal that is a solid is higher up in the electromotive series than the metal that is an ion (dissolved).</span>
Answer:
Substances can change phase—often because of a temperature change. At low temperatures, most substances are solid; as the temperature increases, they become liquid; at higher temperatures still, they become gaseous.
The process of a solid becoming a liquid is called melting. (an older term that you may see sometimes is fusion). The opposite process, a liquid becoming a solid, is called solidification. For any pure substance, the temperature at which melting occurs—known as the melting point—is a characteristic of that substance. It requires energy for a solid to melt into a liquid. Every pure substance has a certain amount of energy it needs to change from a solid to a liquid. This amount is called the enthalpy of fusion (or heat of fusion) of the substance, represented as ΔHfus. Some ΔHfus values are listed in Table 10.2 “Enthalpies of Fusion for Various Substances”; it is assumed that these values are for the melting point of the substance. Note that the unit of ΔHfus is kilojoules per mole, so we need to know the quantity of material to know how much energy is involved. The ΔHfus is always tabulated as a positive number. However, it can be used for both the melting and the solidification processes as long as you keep in mind that melting is always endothermic (so ΔH will be positive), while solidification is always exothermic (so ΔH will be negative).
Answer:
50
Explanation:
so you'll have to apply Newton's 2nd law which is F=ma and then substitute the values that you already have in the question as in, the force is 200 and you'll have to find the acceleration by working it out which is 4m/s² and then find the mass by dividing 200 by 4 so the actual mass is 50kg ✌️❤️
Answer:
d) a pure substance that can be separated into different elements by chemical means.
Explanation:
Hello,
Sodium chloride (NaCl) is a chemical compound composed by sodium and chlorine. They are chemically bonded through a ionic bond which means that the sodium transfers just one electron (valence electron) to the chlorine to form the bond. Now, if we want to separate them, we must induce a chemical process because bond breaking implies a chemical change, not physical. Thus, a typical way to separate them (break the bond) is via electrolysis in which an electric driving force induce the aforementioned breakdown.
Best regards.
