The concentration of Ca2+ ions is half that of the Cl- ions.
1 molecule of NaCl contains 1 sodium ion (Na+), that's why if we have 3.0 moles of.
NaCl, we have 3.0 moles of Na+.
N(ions) = n(mol) · NA.
N(ions) = 3.0 moles · 6.02·1023 = 18.06 ·1023 ions.
The sign's glass absorbed 25466.7 J
<h3>
Further explanation</h3>
Given
The temperature of glass : 23.5 °C to 65.5 °C
mass = 905 g
the specific heat capacity = 0.67 J/g °C
Required
Heat absorbed
Solution
Heat absorbed by sign's glass can be formulated :
ΔT=65.5 - 23.5 = 42
Answer:
Answer E.
For a collision to be completely elastic, there must be NO LOSS in kinetic energy.
We can go through each answer choice:
A. Since the ball rebounds at half the initial speed, there is a loss in kinetic energy. This is NOT an elastic collision.
B. A collision involving sticking is an example of a perfectly INELASTIC collision. This is NOT an elastic collision.
C. A reduced speed indicates that there is a loss of kinetic energy. This is NOT elastic.
D. The balls traveling at half the speed after the collision indicates a loss of kinetic energy, making this collision NOT elastic.
E. This collision indicates an exchange of velocities, characteristic of an elastic collision. We can prove this:
Let:
m = mass of each ball
v = velocity
We have the initial kinetic energy as:
KE = \frac{1}{2}mv^2 + 0 = \frac{1}{2}mv^2KE=21mv2+0=21mv2
And the final as:
KE = 0 + \frac{1}{2}mv^2 = \frac{1}{2}mv^2KE=0+21mv2=21mv2