Answer:
Exothermic reaction: In exothermic reaction, energy is transferred to the surroundings, and the surrounding temperature increases, this is known as exothermic reaction. In other words energy exits in exothermic reaction. Some example of exothermic reactions are:
1) Neutralisation reaction.
2) Combustion reaction.
3) Some oxidation reaction.
Endothermic reaction: In endothermic reaction, energy is taken in from the surrounding, and the surrounding temperature decreases, this is known as endothermic reaction. In other words energy enters in endothermic reaction. Some example of exothermic reactions are:
1) Thermal decomposition.
2) Reaction between citric acid and sodium hydrogen carbonate.
Answer:
T2 = 135.1°C
Explanation:
Given data:
Mass of water = 96 g
Initial temperature = 113°C
Final temperature = ?
Amount of energy transfer = 1.9 Kj (1.9×1000 = 1900 j)
Specific heat capacity of aluminium = 0.897 j/g.°C
Solution:
Formula:
Q = m.c. ΔT
Q = amount of heat absorbed or released
m = mass of given substance
c = specific heat capacity of substance
ΔT = change in temperature
ΔT = T2 - T1
Now we will put the values in formula.
Q = m.c. ΔT
1900 j = 96 g × 0.897 j/g.°C × T2 - 113°C
1900 j = 86.112 j/°C × T2 - 113°C
1900 j / 86.112 j/°C = T2 - 113°C
22.1°C + 113°C = T2
T2 = 135.1°C
Answer:
<em>A not reasonable explanation for an aerospace engineer designs a rocket to have three stages is</em>:
- <u><em>A. To simplify the design of the rocket</em></u>
Explanation:
A <em>three stages rocket</em> permits to separate the fuel compartments. The rocket must be launched with a huge amount of fuel to last the entire travel. Then the initial mass of the rocket and the fuel is considerably large.
As the rocket flies, part of the fuel is consumed and so some compartements may be separated and removed decreasing the mass of the rocket as it flies (<em>option D. </em>is a reasonable explanation), so the rocket only carries the necessary mass (<em>statement B</em>. is a reasonable explanation).
As the rocket moves away from Earth, the gravitational force decreases and, in the space, the amount of thrust needed is lesser, which the aerospace engineers take into account for the design (choice C. is a reasonable explanation).
The only <em>not reasonable explanation to design a three stage rocket</em> is to <em>simplify the design of the rocket</em>: designing a rocket with three modules each with different features, functions, and the detachment mechanisms brings lot of complex problems to solve. So, o<em>ption A. </em>is the correct answer.
Mass:20g
Mole=20/[2(23)+16]
=0.32 mil
