The answer would be D because from my research it's the only one that didn't have a catalyst
A. If motion starts and stops at the same location, then the displacment is zero.
D. Distance is always greater than or equal to the magnitutde of the displacement.
<u>Answer:</u> The reactant ratio in the given chemical equation will be: 
<u>Explanation:</u>
Mole ratio is defined as the ratio of the amount of moles of two substances that are participating in a chemical reaction.
In the given chemical equation:

The reactants are Fe and
and the product is 
The mole ratio is basically the stoichiometric ratio of the chemical compounds taking part in a chemical reaction.
The mole ratio of reactants is stoichiometric ratio of Fe and
, which is:

Hence, the reactant ratio in the given chemical equation will be: 
Answer:
N2
Explanation:
Rate of effusion is defined by Graham's Law:
(Rate 1/Rate 2) = (sqrt (M2)/ sqrt (M1))
(Where M is the molar mass of each substance. )
Molar Mass of oxygen, O2, is 32 (M1).
Rate of effusion of O2 to an unknown gas is .935(Rate 1).
Rate 2 is unknown so put 1.
Solve for x (M2).
.935/1 = sqrt x/ sqrt32
.935 x sqrt 32 = sqrt x
5.29 = sq rt x
5.29^2 = 27.975 = 28
N2 has a molar mass of 28 so it is the correct gas.
Answer:
It increases when the concentration of reactants increases.
Explanation:
Increasing the concentration of reactants in a reaction increases the amount of reacting molecules or ions which would increase the rate of a chemical reaction. Reaction rate does depend on temperature. Increasing temperature also increases reaction rate because particles move faster with the increased kinetic energy to produce more collisions.