Car D
Because it is the heaviest. Kinetic energy is directly proportional to the velocity and mass of the object. All the cars have the same velocity. But Car D has the most mass. So, it has most kinetic energy, because more the mass more the energy.
Answer: A. Energy was absorbed
A balanced equation must have the same number of atoms on the both sides of equation.
Answer:
-162,5 kJ/mol
Explanation:
Cl(g) + 2O2(g) --> ClO(g) + O3(g) ΔH = 122.8 kJ/mol (as we used the reaction in the opposite direction, it will turn the enthalpy from exothermic to endothermic)
2O3(g) --> 3O2(g) ΔH = -285.3 kJ/mol
Cl(g) + O2(g) --> ClO(g) + O3(g) ΔH = 122.8 kJ
+ 2O3 (g) --> 3O2(g) ΔH = - 285.3 kJ
O3(g) + Cl(g) --> ClO(g) + 2O2(g) ΔH = 122.8 + (-285.3) = -162,5 kJ
<u>Answer:</u>
<em>10 is the answer.</em>
<em></em>
<u>Explanation:</u>
Balancing is making the number of atoms of each element same on both the sides (reactant and product side).
To find the number of atoms of each element we multiply coefficient × subscript
For example
contains
5 × 1 = 5 , Ca atoms and
5 × 2 = 10, Cl atoms
If there is a bracket in the chemical formula
For example
we multiply coefficient × subscript × number outside the bracket.......... to find the number of atoms (Please note: 3 is the coefficient, and if there is no number given then 1 will be the coefficient )
So 3 × 3 = 9, Ca atoms
3 × 1 × 2 = 6, P atoms
3 × 4 × 2 = 24, O atoms are present.
Product side contains 
2, K
2, Cl
6, O
So totally 2 + 2 + 6 = 10 atoms present on the product side