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Filtration is commonly used to remove suspended impurities, such as dirt, sand, and other particles, from water. In this process, water is passed through a filter medium that traps the solid impurities while allowing the clean water to pass through.

The valency of an element is determined by the number of electrons it gains or loses to achieve a stable electron configuration. For an element with the electronic configuration 2, 8, 7, the outermost shell (valence shell) has 7 electrons. To achieve stability, it needs 1 more electron to fill the outermost shell, so its valency is 1.

nhydrous cobalt chloride paper is blue in the absence of water. However, when it comes into contact with water, it undergoes a color change to pink due to the formation of hydrated cobalt chloride.

Magnesium chloride is used in antacid medications to relieve heartburn and indigestion. It helps neutralize excess stomach acid.

The atomic number of an element is the number of protons in the nucleus of an atom of that element. The atomic number of aluminium is 13, which means it has 13 protons in its nucleus.

Brass is an alloy made by combining copper with zinc. It is a versatile material with a golden appearance and is used in various applications, including musical instruments, plumbing fittings, and decorative items.

When alkanoic acids react with alcohols in the presence of an acid catalyst, esterification occurs. This chemical reaction forms esters and water.

The carbonyl group (C=O) is the functional group present in alkanals. It consists of a carbon atom double-bonded to an oxygen atom.

According to Boyle's law, when the temperature is constant, the initial pressure multiplied by the initial volume is equal to the final pressure multiplied by the final volume. Mathematically, P1V1 = P2V2, where P1 and V1 are the initial pressure and volume, and P2 and V2 are the final pressure and volume, respectively. Using the given values: (2.0 atm) * (4.0 L) = (1.0 atm) * (V2) Solving for V2: V2 = (2.0 atm * 4.0 L) / (1.0 atm) = 8.0 L

Sulfur dioxide, when released into the atmosphere, can react with water vapor and other atmospheric components to form sulfuric acid (H2SO4), which contributes to the formation of acid rain. Acid rain can have harmful effects on the environment, including damaging aquatic life, forests, and buildings.

The conversion of benzene to toluene involves an electrophilic aromatic substitution reaction. In this reaction, a methyl group (CH3) is added to the benzene ring, replacing one of the hydrogen atoms, and the reaction proceeds through electrophilic attack on the benzene ring.

Water is often referred to as the "universal solvent" because of its ability to dissolve a wide range of substances. This unique property is mainly due to water's polar nature. Water molecules have a slightly positive charge on the hydrogen atoms and a slightly negative charge on the oxygen atom, making it a polar molecule. This polarity allows water molecules to interact with and surround other polar and ionic substances, breaking them down and forming solutions.

A colloid is a type of mixture where one substance is dispersed in another in the form of tiny particles that do not settle out. In milk, fat globules are dispersed in water, forming a colloid.

Aluminum is not hygroscopic. It does not have a strong affinity for water vapor and does not absorb moisture from the air.

To calculate the mass of a substance, we can use the formula: Mass = Volume x Density Given the volume of ethanol is 500 mL and the density of ethanol is 0.789 g/mL, we can plug the values into the formula: Mass = 500 mL x 0.789 g/mL = 394.5 g