Physical changes occur when the properties of a substance are retained and/or the materials can be recovered after the change. Chemical changes involve the formation of a new substance. Formation of a gas, solid, light, or heat are possible evidence of chemical change.
Answer:
C a B r 2 ( a q ) + N a 2 S O 4 ( a q ) ⟶ 2 N a B r ( a q ) + C a S O 4 ( s )
Explanation:
A precipitation reaction is a type of displacement reaction which a precipitate forms. The precipitate would be in the solid state, different from the other products so it can be separated or removed from the reaction.
C a 2 + ( a q ) + S O 4 2 − ( a q ) ⟶ C a S O 4 ( s )
This is wrong because C a S O 4 is the the only product formed.
C a B r 2 ( a q ) + N a 2 S O 4 ( a q ) ⟶ 2 N a B r ( a q ) + C a S O 4 ( s )
This is the correct option, The precipitate is C a S O 4.
C a 2 + ( a q ) + 2 B r − ( a q ) + 2 N a + ( a q ) + S O 4 2 − ( a q ) ⟶ 2 N a + ( a q ) + 2 B r − ( a q ) + C a S O 4 ( s )
This is the ionic equation for the precipitation reaction
Answer:
124.91mL
Explanation:
Given parameters:
P₁ = 1.08atm
V₁ = 250mL
T₁ = 24°C
P₂ = 2.25atm
T₂ = 37.2°C
V₂ = ?
Solution:
To solve this problem, we are going to apply the combined gas law;

P, V and T represents pressure, volume and temperature
1 and 2 delineates initial and final states
Convert the temperature to kelvin;
T₁ = 24°C, T₁ = 24 + 273 = 297K
T₂ = 37.2°C , T₂ = 37.2 + 273 = 310.2K
Input the variables and solve for V₂

V₂ = 124.91mL
Answer:
A. There is more dissolved oxygen in colder waters than in warm water.
D. If ocean temperature rise, then the risk to the fish population increases.
Explanation:
Conclusion that can be drawn from the two facts stated above:
*Dissolved oxygen is essential nutrient for fish survival in their aquatic habitat.
*Dissolved oxygen would decrease as the temperature of aquatic habit rises, and vice versa.
*Fishes, therefore, would thrive best in colder waters than warmer waters.
The following are scenarios that can be explained by the facts given and conclusions arrived:
A. There is more dissolved oxygen in colder waters than in warm water (solubility of gases decreases with increase in temperature)
D. If ocean temperature rise, then the risk to the fish population increases (fishes will thrive best in colder waters where dissolved oxygen is readily available).
<span>This is an example of a substance changing state, a physical change, the molecules are changed, but the atoms themselves do not change, just their arrangement, and the mass of the molecules is the same. Therefor energy is absorbed by the molecules, as energy is required to change the state or physicality of a molecule structure.Hope this helps. Let me know if you need additional help!</span>