Answer:
Sodium oxide + Water - - - > Sodium Hydroxide.
The answer should be (D) endothermic reaction.
Reason : - Reactions in which energy is absorbed are called endothermic reactions. In your provided question, 150 kcal energy is being <u>absorbed</u>, and thus, we can say that it is an endothermic reaction.
Correct answer is <span>C. They have a full shell of valence electrons. </span>
A) -0.5(9.8)*t^2 = -25(t-2) - 0.5(9.8)(t-2)^2
-4.9t^2 = -25t + 50 - 4.9(t^2-4t+4)
0 = -25t+50+19.6t - 19.6
5.4t = 30.4
t = 5.62962963 s
b) h = -4.9(5.62962963)^2
h = -155.2943759
the building is 155.2943759 m high
c) speed 0of first stone
= at
= 9.8*5.62962963
= 55.17037037 m/s
speed of second stone
= v + at
= 25+9.8*3.62962963
= 60.57037037 m/s