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Ethene can be gotten from the dehydration of ethanol in the presence of excess \(H_{2}SO_{4}\) or \(H_{3}PO_{4}\).

The equilibrium position is shifted to the left with a decrease in pressure in this system because the number of gaseous molecules on the right is less. (Le-Chatelier's principle).

The preferential discharge of ions is influenced by: - The position of the ions in the electrochemical series - The concentration of the ions in the electrolyte - The nature of the electrode

\(_{12}Mg = 2, 8, 2\) \(= 1s^{2} 2s^{2} 2p^{6} 3s^{2}\)

Stainless steel comprises iron (Fe), chromium (Cr), manganese (Mn), silicon (Si), carbon (C) and, in many cases, significant amounts of nickel (Ni) and molybdenum (Mo).

\(1mole = 6.02 \times 10^{23} ions\) \(0.02moldm^{-3} = 0.02 \times 6.02 \times 10^{23}\) =\(0.1204 \times 10^{23} = 1.204 \times 10^{22}\) \(\approxeq 1.2 \times 10^{22}\)

In order to extinguish a petrol fire, you have to cut off the oxygen. This can be done by using carbon dioxide gas to dilute the oxygen available and stop the burning.

Using n = cv where n = no of mole, c = molar concentration(mol/dm3) and v = volume( dm3) volume = 500\(cm^{3}\) = 0.5dm3, c = 0.005\(moldm^{-3}\) number of mole(n) = c x v = 0.5 X 0.005 = 0.0025mol. but n = \(\frac{mass}{ molar mass}\) = 0.0025 = \(\frac{mass}{ 98}\) (where 98g/mol is the molar mass of H2SO4) mass of H2SO4 = 0.0025 x 98 = 0.245g.

The easiest and most drastic way to change the boiling point is by tampering with the pressure above your water. To lower the boiling point, you need simply to decrease its external pressure.

From the graph, check for their point of intersection and trace it down to the temperature axis.

The point of saturation is the point it gets to and from thence, the solution can no longer take in the salt anymore. From this point, it begins to form precipitate while the solution remains unchanged.

Thus bromine water will be decolorized by alkynes due to the presence of two pi bonds available for reaction!

Photosynthesis is the process of food-making in plants, it doesn't have any by-products that pose a threat to the environment. Infact, the plants use our waste product of respiration (Carbon dioxide) and uses it for the photosynthetic process and gives off oxygen as by-product.

The position of equilibrium will shift under the effects of changes in temperature, pressure and concentration.

Heat energy near the ice gets absorbed into the ice. The energy breaks the bonds of the ice, causing it to melt into liquid water. On other words, when ice melts, the energy gets absorbed into the water.