Answer:
B. choosing a material that will show warning before it fails.
Explanation:
Answer:
B) -4.1 units
Explanation:
According to this question, a state property X has a value 89.6 units. It undergoes the certain changes as follows:
- first increase by 3.6 units
- then increase by another 18.7 units
- then decrease by 12.2 units
- and finally attains a value of 85.5 units
This can be mathematically represented by 89.6 - {3.6 + 18.7 - 12.2 - x) = 85.5
To get x, we say;
89.6 + 3.6 = 93.2
93.2 + 18.7 = 111.9
111.9 - 12.2 = 99.7
99.7 - 85.5 = 14.2units.
The changes that occured is represented as follows:
= (3.6 + 18.7) - (12.2 + 14.2)
= 22.3 - 26.4
= -4.1 units
Answer:
1. 0.97 V
2. 
Explanation:
In this case, we can start with the <u>half-reactions</u>:
With this in mind we can <u>add the electrons</u>:
<u>Reduction</u>
<u>Oxidation</u>
The reduction potential values for each half-reaction are:
- 0.69 V
-1.66 V
In the aluminum half-reaction, we have an oxidation reaction, therefore we have to <u>flip</u> the reduction potential value:
+1.66 V
Finally, to calculate the overall potential we have to <u>add</u> the two values:
1.66 V - 0.69 V = <u>0.97 V</u>
For the second question, we have to keep in mind that in the cell notation we put the anode (the oxidation half-reaction) in the left and the cathode (the reduction half-reaction) in the right. Additionally, we have to use "//" for the salt bridge, therefore:
I hope it helps!
Answer:
Reaction 5: Decomposition reaction.
Reaction 6: Single replacement reaction
Reaction 7: Combination reaction.
Reaction 8: Combustion reaction.
Explanation:
<u><em>Reaction 5:</em></u> 2KClO₃ → 2KCl + 3O₂.
- It is a decomposition reaction.
- A decomposition reaction is a type of chemical reaction in which a single compound breaks down into two or more elements or new compounds.
- In this reaction: potassium chlorate decomposes into two single components (potassium chloride and oxygen).
- So, it is a decomposition reaction.
<u><em>Reaction 6:</em></u> Zn + 2HCl → H₂ + ZnCl₂.
- It is a single replacement reaction.
- A single-replacement reaction, a single-displacement reaction, is a reaction by which one (or more) element(s) replaces an/other element(s) in a compound.
- It is most often occur if element is more reactive than the other, thus giving a more stable product.
- In this reaction, zinc metal (more active) displaces the hydrogen to form hydrogen gas and zinc chloride, a salt. Zinc reacts quickly with the acid to form bubbles of hydrogen.
<u><em>Reaction 7:</em></u> N₂O₅ + H₂O → 2HNO₃.
- It is a combination "synthesis" reaction.
- A synthesis reaction has two or more reactants and only one product.
- In this reaction, dinitrogen pentoxide reacts with water to produce nitric acid.
- So, it is considered as a synthetic "combination" reaction.
<u><em>Reaction 8:</em></u> 2C₂H₆ + 7O₂ → 4CO₂ + 6H₂O.
- It is a combustion reaction.
- A combustion reaction is a reaction where hydrocarbon alkane is completely burned in oxygen to produce water and carbon dioxide.
- In this reaction 1.0 mole of ethane is burned to give 4.0 moles of carbon dioxide and 6.0 moles of water.
- So, it is considered as a combustion reaction.
