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
Answer:
1.428 moles
Explanation:
If 0.0714 moles of N2 gas occupies 1.25 L space,
how many moles of N2 have a volume of 25.0 L?
Assume temperature and pressure stayed constant.
we experience it 0.0714 moles: 1.25L space
x moles : 25L of space
to get the x moles, cross multiply
(0.0714 x 25)/1.25
1.785/1.25 = 1.428 moles
Answer:
cold
Warm air lifted over a moving cold air mass will produce a _____ front.
1) The answer is: 2 moles of oxygen molecules.
Balanced chemical reaction of methane combustion:
CH₄(g) + 2O₂(g) → CO₂(g) + 2H₂O(g).
Coefficients with the lowest ratio indicate the relative amounts of substances in a reaction.
In fronf of oxygen molecule is coefficient 2.
2) The answer is: 4 moles of oxygen atoms.
In one molecule of oxygen there are two oxygen atoms, so in two molecules there are four oxygen atoms.
First we need to calculate the number of moles of FeS
:
number of moles = mass (grams) / molecular mass (g/mol)
number of moles of FeS = 198.2/120 = 1.65 moles
From the chemical reaction we deduce that:
if 4 moles of FeS produces 8 moles of SO
then 1.65 moles of FeS produces X moles of SO
X = (1.65×8)/4 = 3.3 moles of SO
Now we can calculate the mass of SO:
mass (grams) = number of moles × molecular mass (grams/mole)
mass of SO = 3.3×64 = 211.2 g
