Answer:
B: Igneous, C: Metamorphic, D: Sedimentary
Explanation:
Sorry, i dont know A
<span>An example of sublimation is when a dry ice changes to carbon dioxide when kept in an open container. Sublimation is a change from solid phase to gas phase without passing through the liquid state. In this example, it is clear that the dry ice is solid form and it evaporates as gas without passing through the liquid state.</span>
Answer:
Explanation:
To calculate the cell potential we use the relation:
Eº cell = Eº oxidation + Eº reduction
Now in order to determine which of the species is going to be oxidized, we have to remember that the more the value of the reduction potential is negative, the greater its tendency to be oxidized is. In electrochemistry we use the values of the reductions potential in the tables for simplicity because the only thing we need to do is change the sign of the reduction potential for the oxized species .
So the species that is going to be oxidized is the Aluminium, and therefore:
Eº cell = -( -1.66 V ) + 0.340 V = 5.06 V
Equally valid is to write the equation as:
Eº cell = Eº reduction for the reduced species - Eº reduction for the oxidized species
These two expressions are equivalent, choose the one you fell more comfortable but be careful with the signs.
Answer:
6 C(s) + 3 O₂(g) + 2 Fe₂O₃(s) → 4 Fe(s) + 6 CO₂(g)
Explanation:
Iron can be formed in two steps.
Step 1: 2 C(s) + O₂(g) → 2 CO(g)
Step 2: Fe₂O₃(s) + 3 CO(g) → 2 Fe(s) + 3 CO₂(g)
In order to get the net chemical equation, we will multiply the first step by 3, the second step by 2, and then add them.
6 C(s) + 3 O₂(g) → 6 CO(g)
+
2 Fe₂O₃(s) + 6 CO(g) → 4 Fe(s) + 6 CO₂(g)
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6 C(s) + 3 O₂(g) + 2 Fe₂O₃(s) + 6 CO(g) → 6 CO(g) + 4 Fe(s) + 6 CO₂(g)
6 C(s) + 3 O₂(g) + 2 Fe₂O₃(s) → 4 Fe(s) + 6 CO₂(g)
The given question is incomplete. The complete question is as follows.
Which of the following best helps explain why an increase in temperature increases the rate of a chemical reaction?
(a) at higher temperatures, high-energy collisions happen less frequently.
(b) at low temperatures, low-energy collisions happen more frequently.
(c) at higher temperatures, less-energy collisions happen less frequently.
(d) at higher temperatures, high-energy collisions happen more frequently
Explanation:
When we increase the temperature of a chemical reaction then molecules of the reactant species tend to gain kinetic energy. As a result, they come into motion which leads to more number of collisions within the molecules.
Therefore, chemical reaction will take less amount of time in order to reach its end point. This means that there will occur an increase in rate of reaction.
Thus, we can conclude that the statement at higher temperatures, high-energy collisions happen more frequently, best explains why an increase in temperature increases the rate of a chemical reaction.
