1. Pure substances cannot be separated into any other kinds of matter, while a mixture is a combination of two or more pure substances.
2. A pure substance has constant physical and chemical properties, while mixtures have varying physical and chemical properties (i.e., boiling point and melting point).
3. A pure substance is pure, while a mixture is impure.
112.5 g. The production of 50.00 g O2 requires 112.5 g H2O.
a) Write the partially balanced equation for the decomposition of water.
MM = 18.02 32.00
2H2O → O2 + …
Mass/g = 50.00
b) Calculate the <em>moles of O2
</em>
Moles of O2 = 50.00 g O2 × (1 mol O2/16.00 g O2) = 3.1250 mol O2
c) Calculate the <em>moles of water</em>
Moles of H2O = 3.1250 mol O2 × (2 mol H2O/1 mol O2)
= 6.2500 mol H2O
d) Calculate the mass of water
Mass of H2O = 6.2500 mol H2O × (18.02 g H2O/1 mol H2O)
= 112.5 g H2O
Answer: II. The catalyst provides a new pathway in the reaction mechanism.
III. The catalyst speeds up the reaction.
Explanation:
Activation energy is the extra energy that must be supplied to reactants in order to cross the energy barrier and thus convert to products.
A catalyst is a substance which increases the rate of a reaction by taking the reaction through a different path which involves lower activation energy and thus more molecules can cross the energy barrier and more molecules convert to products.
The catalyst itself does not take part in the chemical reaction and gets regenerated as such at the end of the reaction without getting consumed.
answer of this question is [Ar]3d8 4s2
