Here, Molar mass of N2O4 = 92.02 g/mol
So, Number of molecules in 1 mole (92.02 g) = 6.023 * 10²³
Number of molecules in 76.3 g = 6.023 * 10²³ / 92.02 * 76.3
= 6.023 * 10²³ / 1.20
= 5 * 10²³
In short, Your Answer would be approx. 5 * 10²³ molecules
Hope this helps!
Explanation:
1. The three factors are;
- Increasing the surface area of the reactants
- Using a catalyst
- Increasing temperature
2. Raising the temperature of a reaction mixture is the same as increasing the kinetic energy of the reacting molecules.
3. This reaction is an exothermic reaction. In exothermic reaction, the temperature of the system (mixture) decreases while that of the surroundings increases.
4. Reactions that releases energy to the surroundings are exothermic reactions.
5. All the options is an example of exothermic process because heat is being removed from the system except;
B. Evaporation of water - This is because it must absorb heat from the surroundings making it endothermic.
Answer: 
Explanation: According to law of conservation of mass, mass can neither be created nor be destroyed.
Thus the mass of products has to be equal to the mass of reactants. The number of atoms of each element has to be same on reactant and product side. Thus chemical equations are balanced.
This is an example of combustion reaction in which hydrocarbon reacts with oxygen to form carbon dioxide and water. This is an exothermic reaction in which a large amount of heat is liberated, thus water also exists as vapors.

Answer:
Chloro-Flouro-Carbon
Explanation:
Chloro-Flouro-Carbon (CFC Gas) is used as a refrigerant in fridges and freezers.
There are several types of surfactants, to name two: alkylbenzene sulfonates or detergents; and lauryl sulfate or foaming agents.
Alkylbenzene sulfonates are commonly used in the production of detergent soaps, these help clean the dirt from cloths and other materials, it also produces foam.
Lauryl sulfate or foaming agents are commonly used in the production of dishwashing liquid or handwashing soap.