1. Make a Prediction
2. Fill both beakers with water
3. Dissolve salt in one of the beakers
4. Place both in the freezer and observe
5. Write a report
(Always make the prediction first! That's a hypothesis!)
4) fission is a nuclear reaction where the nucleus of a reactant breaks apart
<span>People with protanopia are unable to sense any ‘red’ light, people with deuteranopia do not sense ‘green’ light and people with tritanopia cannot sense ‘blue’ light. If a person perceives the color green, then the yellow sensitive nerves must work somewhat effectively since green is a combination of yellow and blue. Red-sensitive nerves are most likely not responding properly for this person. The answer is C.</span>
Answer: CuI₂ + Br₂
Explanation:
1) The activity series F > Cl > Br > I means that F is the most active and I is the least active of those four elements (the halogens, group 17 in the periodic table).
The activity is a measure of how eager is an element to react compared to other elements in the series in a single replacement reaction.
2) Choice 1: CuI₂ + Br₂
Since the activity of Br is higher than that of I, Br will react with CuI₂, displacing I, which will be left alone, as per this chemical equation:
CuI₂ + Br₂ → CuBr₂ + I₂
Being I less active than Br, it cannot displace Br in CuBr₂.
3) Choice 2: Cl₂ + AlF₃
Being Cl less active than F, the former will not displace the latter, and the reaction will not proceed.
4) Choice 3: Br₂ + NaCl
Again, being Br less active than Cl, the former will not displace the latter, and the reaction will not proceed.
5) Choice 4: CuF₂ + I₂
Once more, being I less active than F, the former will not displace the latter, and the reaction will not proceed.
Answer:
Chemicals A and B form an endothermic reaction, and chemicals C and D form an exothermic reaction.
Explanation:
The reaction that produced chemical C is an endothermic reaction whereas, the reaction between C and D is an exothermic one.
An exothermic change is one in which heat is liberated to the surroundings. So the surrounding becomes hotter at the end of the reaction.
An endothermic reaction is a change in which heat is absorbed from the surrounding and hence the surrounding colder at the end of the change.
- We can see that the first reaction is endothermic.
- The second reaction is exothermic.