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Combustion of propane, burning of methane and the decomposition of hydrogen peroxide into water and oxygen are all exothermic reaction because heat is given off from the system to the environment. However, only formation of table salt from Sodium and Chlorine is endothermic reaction, as the reaction is a simple combination reaction. The formation of sodium chloride (NaCl) is an endothermic reaction because it requires energy in several steps, including: Sublimation: Sodium metal sublimates, or turns directly from a solid to a gas, without becoming a liquid first. This is an endothermic process. Ionization: Sodium atoms lose an electron to become Na+ ions, which is also endothermic. Dissociation: The chlorine molecule splits into two chlorine atoms, which is endothermic. Conversely, the formation of sodium chloride is not entirely endothermic, however, because the final step of the process is exothermic: Ionic lattice formation: The Na+ and Cl- ions come together to form the ionic lattice of sodium chloride, releasing a large amount of energy.

If a reaction is reversed, the equilibrium constant (Kc) for the reversed reaction becomes the reciprocal of the original equilibrium constant. For a reaction: A + B ⇌ C + D The equilibrium constant Kc = [C][D]/[A][B] For the reversed reaction: C + D ⇌ A + B The equilibrium constant Kc(reversed) = [A][B]/[C][D] Thus, Kc(reversed) = 1/Kc.

Both soap and detergent molecules have a hydrophilic (water-attracting) head and a hydrophobic (water-repelling) tail. The hydrophilic head allows the molecules to interact with water, while the hydrophobic tail interacts with oils and grease.

The solubility product constant (Ksp) is a constant specific to a given solute and solvent at a particular temperature. It is used to calculate the concentration of a solute in a saturated solution, where no more solute can dissolve at equilibrium.

Carbon dioxide (CO2) is a trace gas in the atmosphere, but it plays a significant role in the greenhouse effect. It absorbs and traps heat from the Earth's surface, contributing to global warming.

Temporary hardness in water can be removed by boiling. When water is boiled, the calcium and magnesium bicarbonates decompose, forming insoluble calcium carbonate (CaCO3) and magnesium carbonate (MgCO3), which precipitate out of the water.

Faraday's constant is a proportionality constant that relates the amount of electric charge (in coulombs) required to liberate or deposit one mole of substance during an electrolytic reaction. Its value is approximately 96,485 C/mol.

According to Boyle's law (for constant temperature), the product of initial pressure and initial volume is equal to the product of final pressure and final volume. Therefore, (1.5 liters) \times (2 atmospheres) = (new volume) \times (4 atmospheres). Solving for the new volume gives us (new volume) = (1.5 liters \times 2 atmospheres) / 4 atmospheres = 0.75 liters.

Stainless steel is an alloy composed of iron and chromium, with small amounts of other elements like nickel and molybdenum. The addition of chromium provides stainless steel with excellent corrosion resistance.

In the gas state of matter, particles are widely spaced and move freely with high kinetic energy. Gases do not have a definite shape or volume and will fill the entire available space.

The reducing agent is the species that undergoes oxidation and causes the reduction of another species. In this reaction, zinc (Zn) is being oxidized to form zinc sulfate (ZnSO\(_4\)) while reducing copper sulfate (CuSO\(_4\)) to copper (Cu).

To balance the redox reaction, we need to ensure that the number of atoms of each element and the total charge are the same on both sides of the equation. In this reaction, we can see that the number of oxygen (O) atoms is not balanced. To balance them, we need to add a coefficient of 3 in front of CO\(_2\) to get 3CO\(_2\). Similarly, the number of iron (Fe) atoms is not balanced. To balance them, we need to add a coefficient of 2 in front of Fe to get 2Fe

Ionization energy generally increases from left to right across a period. Ionization energy is the energy required to remove an electron from a neutral atom, and as you move from left to right, the atomic size decreases, making it harder to remove an electron, and thus, the ionization energy increases.

Ionic bonding occurs between a metal and a non-metal. The metal atom donates one or more electrons to the non-metal atom, resulting in the formation of positively charged cations and negatively charged anions. These oppositely charged ions are held together by electrostatic forces to form an ionic compound.

Pentane (C5H12) is a straight-chain alkane. Alkanes are hydrocarbons with the general formula CnH2n+2. They are called straight-chain alkanes if all the carbon atoms are connected in a continuous chain without any branches. Butane and Isobutane are both C4H10, but Isobutane has a branched structure, not a straight chain. Cyclopentane (C5H10) is a cycloalkane, not a straight-chain alkane.