Answer:
C) 1 x 10-10 M
Explanation:
To solve this question we must use the equation:
Kw = [H+] [OH-]
<em>Where Kw is the equilibrium dissociation of water = 1x10-14</em>
<em>[H+] is the molar concentration of hydronium ion = 1x10-4M</em>
<em>[OH-] is the molar concentration of hydroxyl ion</em>
<em />
Replacing:
1x10-14= 1x10-4 [OH-]
<em>[OH-] = 1x10-14 / 1x10-4M</em>
<em>[OH-] = 1x10-10 M</em>
Right option is:
<h3>C) 1 x 10-10 M
</h3>
I feel like it is important, because it is always nice to learn about
new things and keep your mind open, to expand your knowledge.
I hope this helps ^-^
Answer:
First confirm the reaction is balanced:
C3H8 + 5O2 --> 3CO2 + 4H20 (3 cabon - check; 8 hydrogen - check; 10 oxygen - check).
a) In the equation there is a 5:1 ratio between propane and oxygen. We also know that number of mole is proportional to pressure and volume. Since pressure is constant (STP) then the volume of O2 is 7.2 * 5 = 36 litres.
b) For a near ideal gas that PV = nRT (combined gas law). So for 7.2 litres propane we find n(propane) = 101.3 * 7.2/8.314*298 ~ 0.29 mole (using metric units throughout for simplicity).
There is a 1:3 ratio between propane and CO2. Therefore 3 * 0.29 = 0.87 mole of CO2 is produced.
MW(CO2) ~ 44 g/mol. Therefore m(CO2) = 44 * 0.87 ~ 38.3 g
c) We know we need more oxygen than propane (due to the 1:5 ratio) so oxygen is the limiting reagent. Again Volume is proportional to number of mole and we see there is a 5:4 ratio between oxygen and water. Therefore the volume of water vapour produced will be (4/5) * 15 = 12 litres.
The other questions use the same technique and will give you some much needed practice.
Explanation:
Explanation:
The law of conservation of mass states that mass is conserved which also means that it cannot be created or destroyed within the isolated system.
We can add the mass of the reactant and can be equal to the mass of the product. But in some cases, it will not work like:
If reactants are not in the mole ratio, there will be a limiting reagent.
If a gas is one of reactants or products.
Radioactive decay and nuclear reactions(fission or fusion).
