Answer:
d). A catalyst lowers the activation energy for a chemical reaction.
Explanation:
From the given choices, it is true that a catalyst lowers the activation energy for a chemical reaction.
The activation energy is the energy barrier that must be overcome before a chemical reaction can occur.
Some reactions have very high activation energy and would not occur without the introduction of a catalyst.
The catalyst brings the reactants into contact by removing the energy deficiency in the system.
Answer:
R.F.M of Iron (II) oxide :

Moles :

Molecules :

Answer:
Solution Concentration: Molarity Moles of solute in one liter of solution Used because it describes how many molecules of solute are in each liter of solution Tro: Chemistry: A Molecular Approach, 2/e 6 amount of solute (in moles) Molarity, M = amount of solution (in L) moles of solute M = L of solution or simply 4
GOOD LUCK!!
I think the correct answer from the choices listed above is option A. A can of diet soda will float in water while a can of regular sugar soda will sink. This is due to the reason that the regular soda is more dense than the diet soda. Hope this answers the question.