Answer:
The sublimation energy
Explanation:
When an ionic solid turns into a gas it is changing from solid state to gas state without going throught liquid state. This process is called sublimation and the energy will be equal to
Answer: the theory that all matter us made up of tiny invisible particles. Hope that help you out :)
Explanation:
The reaction is:
2 NO₂ (g) + F₂ (g) ⇆ 2 NO₂F (g)
The stoichiometric coefficients of the substances balance out each other to obey the Law of Definite Proportions. Now, you have to note that determining the reaction rate expression is specific to a certain type of reaction. So, this are determined empirically through doing experiments. But in chemical reaction engineering, to make things simple, you assume that the reaction is elementary. This means that the order of a reaction with respect to a certain substance follows their individual stoichiometric coefficients. What I'm saying is, the stoichiometric coefficients are the basis of our reaction rate orders. For this reaction, the rate order is 2 for NO₂, 1 for F₂ and 2 for NO₂F. When the forward and reverse reactions are in equilibrium, then it applies that:
Reaction rate of disappearance of reactants = Reaction rate of formation of products.
Therefore, we can have two reaction rate constants for this. But since the conditions manipulated are the reactant side, let's find the expression for reaction rate of disappearance of reactants.
-r = k[NO₂]²[F₂]
The negative sign before r signifies the rate of disappearance. If it were in terms of the product, that would have been positive. The term k denotes for the reaction rate constant. That is also empirical. As you can notice the stoichiometric coefficients are exponents of the concentrations of the reactants. Let's say initially, there are 1 M of NO₂ and 1 M of F₂. Then,
-r = k(1)²(1)
-r = k
Now, if we change 1 M of NO₂ by increasing it to its half, it would now be 1.5 M NO₂. Then, if we quadruple the concentration of F₂, that would be 4 M F₂. Substituting the values:
-r = k(1.5)²(4)
-r = 9k
So, as you can see the reaction rate increase by a factor of 9.
Answer:
Is pink in base solution, it provides a visual signal that a solution has changed from acid to a base, is colorless in acid solution.
Explanation:
As all the indicator, phenolphtalein has the property that turns pink when the solution that you have reaches a value of a pH of 9 or above. From 0 to 8 in a pH scale, is colorless. This point in which an indicator changes is it called equivalence point.