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.
Gunpowder is a heterogenous mixture,
Reason : the composiotion of the mixture is not uniform throughout, the mixture can be separated by a suitable method , and finally , it composes of charcoal, sulfur and potassium nitrate which is not homogeneous mixture.
Answer: D. An increase in entropy
Explanation:
Entropy is the measure of randomness or disorder of a system. If a system moves from an disordered arrangement to an ordered arrangement, the entropy is said to increase and vice versa.
For a reaction to be spontaneous, the enthalpy of the solution must decrease and the entropy must increase.
To overcome a positive enthalpy of solution and allow a solid solute to dissolve in water, an increase in entropy would make the reaction spontaneous as the system would move to a more disordered state.
Answer:
The sum of the molar masses of each isotope of the element.
