Answer:
Total energy is 170 kJ
Explanation:
Given data:
latent heat of fusion of alcohol is 25 kcal/kg
melting point of alcohol is -114 degree c
specific heat us 0.60 k cal/kg degree c
energy need for 2 kg solid alcohol is
for Melting:
Energy Q is calculated as
Energy, Q = 25 \times 2.0 kg = 50 kJ
Energy required for Heating liquid:
Energy, ΔH = 2.0 kg \times 0.60 \times (100°C) = 120 kJ
Total energy = (50 kJ + 120 kJ) = 170 kJ
It's just in the name! Accurate data is helpful, and correct, but reproducible data is all of that, and is able to be given to other people through different sources! At least, that's what my understanding of them are. Hope it helps!
Answer:
The correct option is : Their atoms have eight electrons in their valence shells, so noble gases are very unreactive.
Explanation:
The octet rule state that atoms tend to complete their last energy levels with eight electrons, and that this configuration make them very stable and unreactive.
Noble gases are characterized as unreactive atoms, and this is associated with the fact that they have a complete valence shell, it means that they have eight electrons on it (they follow the octet rule).
Atoms with less electrons on their valence shells tend to react with another atom, forming bonds, to complete their valence shells (with eight electrons).
Answer: 
The ball was thrown at the speed of
.
Maximum height achieved is 
Time of flight is t.
Now, the time the ball takes to achieve maximum height = the time taken by ball to fall back = 
let us just consider the second half of the flight. At
, the velocity would be zero. let us consider as the initial velocity for the second half of the flight i.e. 
Using the equation of motion:

where,
is the final velocity, a is the acceleration, t is the time taken.
Because the ball would fall under gravity, hence a=g and time of flight would be t/2

The magnitude of the force<span> a 1.5 x 10-3 C charge exerts on a 3.2 x 10-4 C charge located 1.5 m away is 1920 Newtons. The formula used to solve this problem is:
F = kq1q2/r^2
where:
F = Electric force, Newtons
k = Coulomb's constant, 9x10^9 Nm^2/C^2
q1 = point charge 1, C
q2 = point charge 2, C
r = distance between charges, meters
Using direct substitution, the force F is determined to be 1920 Newtons.</span>