Answer:
1.13×10^25 molecules of water.
Explanation:
Equation of the reaction;
C8H18(g) + 25/2 O2 (g) -------> 8CO2(g) + 9H2O(l)
It is important to first put down the balanced reaction equation. It is not possible to solve any problem on stoichiometric relationship without a balanced reaction equation. Once the equation is obtained, we can now proceed with other steps in the solution of the problem.
From the reaction equation, 1 mole of C8H18 produces 9 moles of water
1 mole of C8H18 occupies 22.4L volume while 1 mole of water contains 6.02×10^23 molecules of water
Hence
22.4 L of C8H18 produces 9(6.02×10^23) molecules of water
46.72 L of C8H18 will produce 46.72 L × 9(6.02×10^23) molecules of water/22.4 L
= 113×10^23 or 1.13×10^25 molecules of water.
The answer should be D. A rate law needs to be rate equaling the rate constant which is represented as k (make sure you use a lower case k since an upper case K is for equilibrium) times the concentrations of each reactant raised to the power of what ever order it has. (if A was a zero order it would be [A]⁰ and if A was third order it would be [A]³).
Do not get the order the reactants are confused with the coefficients in the chemical equation. (just because the reaction has 2B does not mean the rate law will have [B]². As shown in this example since it is first order therefore being [B] in the rate law)
I hope this helps. Let me know if anything is unclear in the comments.
Oxidation
iron+oxygen happened
Answer:
1. Changing Beam Material
2. Corrugation
3. Changing Beam form
4. Steel Reinforcing Bars
Explanation:
Changing Beam Material
Some materials are stronger when used in beams than others. Beams made of steel for instance are stronger than beams made of wood. Therefore changing material can improve the strength of the beam. It is quite important to take into account the weights of the material though as different structures have different requirements.
Corrugation.
You can fold the beam into triangular shapes to increase strength. If you look at roofs you will notice that they are folded and this increased their strength. The same logic can be applied to beams.
Changing Beam Form
Another way to make Beams stronger is to change their form or rather their shape. Straight beams are not as strong as I-beams for instance. I-beams look like the capital letter I with the lines at both ends. I-beams are usually used in construction which shows that they are quite strong.
Steel Reinforcing Bars
When placed in concrete beams, Steel Reinforcing Bars which are also called Rebar can help strengthen a beam by helping it withstand the forces of tension. A concrete beam with Rebar inside it is known as Reinforced Concrete.
