Answer:
0.87
Explanation:
Given :
Mass of bottle = 29.2 g
Mass when filled with diesel = 116.2 g
Mass when filled with water = 129.2 g
The mass of water = (Mass when filled with water - mass of bottle)
Mass of water = 129.2 - 29.2 = 100 g
Mass of diesel = (Mass when filled with diesel - mass of bottle)
Mass of diesel = 116.2 - 29.2 = 87
Relative density of diesel = mass of diesel / mass of equal volume of water
Relative density = 87 / 100 = 0.87
B. The flask would probably feel warmer than before the reaction started.
C. The flask would feel the same as before the reaction started.
D. none of the above
Answer: A. The flask would probably feel cooler than before the reaction started.
Explanation: An endothermic reaction is a type of of chemical reaction in which energy is absorbed from the surroundings. The temperature of the surrounding decreases.
An Exothermic reaction is a type of of chemical reaction in which energy is released into the surrounding. The temperature of the surrounding increases.
When an endothermic reaction takes place in the flask, the heat is absorbed by the flask and thus the temperature of the surrounding (here the flask) will decrease which can be felt by touching the outside of the test tube. Thus the flask would appear colder.
CCA Unit 3: Heat Energy and Reactions Unit Test Answers
Please keep in mind these are for CHECKING YOUR ANSWERS, not for using as an answer key to cheat!!
1. A
2. C
3. A
4. A
5. C
6. D
7. C
8. C
9. A
10. A
11. C
12. A
13. C
14. C
15. C
16. B
17. D
18. B
19. Q= = mass * specific heat * delta T 343 = 55.0 * specific heat (86.0-19.0) 343=3685 * specific heat specific heat = 0.0931 cal/g Celsius
20. Temperature is absolute while heat is relative. The direction of heat always travels to the warmer temperature of the object to the cooler one.
21. Ke=[C]^2/[A]^3[B}^2
22. A chemical reaction is spontaneous if an increase in the total entropy of the system and surroundings accompanies it.
Example:
4 Fe + 3 O 2 -> Fe 2 O 3
Enjoy guys ;)
annihilate each other?
(1) 1.64 × 10^–13 J (3) 5.47 × 10^–22 J
(2) 8.20 × 10^–14 J (4) 2.73 × 10^–22 J
Answer:
(1)
Explanation:
Energy released in this process is given by
here we have
since here mass of two electrons converted into energy so we have
so here energy released is the energy of rest mass energy due to two charges i.e. electrons and positrons
The minimum total energy released when an electron and its antiparticle (positron) annihilate each other is 1.64 x 10⁻¹³ J.
The minimum total energy released when an electron and its antiparticle (positron) annihilate each other is calculated as follows;
E = Δmc²
where;
E = (2 x 9.11 x 10⁻³¹) x (3 x 10⁸)²
E = 1.64 x 10⁻¹³ J
Learn more about energy here: brainly.com/question/25959744
#SPJ5
Answer:
12 A
Explanation:
Voltage, V = 120 V
Resistance, R 10 ohm
By using ohm's law
V = i x R
where, i is the current
i = V / R
i = 120 / 10
i = 12 A
thus, the current is 12 A.
Answer: 200 W
Explanation:
In physics, power is defined as the amount of work done divided by the time taken to do that work:
where W is the work done and t is the time.
In this problem, the work done is W=600 J, while the time taken is t=3 s. Substituting into the formula, we find the power: