S-Block Elements Quiz

Beryllium oxide is a unique alkaline earth metal oxide that can react with both acids and bases, behaving like both a base and an acid.

The tendency of alkaline earth metal hydroxides to dissolve in water, their stability when heated, and their basic character increases as you move down the group from Mg to Ba.

All alkaline earth metal oxides except BeO are basic in nature, meaning they react with water to form hydroxides. This happens due to the increasing size and less electronegativity of the elements down the group.

Beryllium reacts with oxygen upon heating to form beryllium oxide (BeO). This reaction is exothermic and results in a white powder that is very stable.

Magnesium reacts with both oxygen (O2) and nitrogen (N2) in air upon heating to form magnesium oxide (MgO) and magnesium nitride (Mg3N2). The reaction is highly exothermic.

All alkaline earth metals, except beryllium, react with hydrogen upon heating to form hydrides with the formula MH2. These hydrides are ionic, meaning they are made of a metal cation and a hydride anion.

Beryllium forms a chloride-bridged dimer in the vapor phase, but this structure breaks down into a linear monomer at high temperatures.

The solubility, thermal stability, and basic strength of alkaline earth metal hydroxides increase as you move down the group from Mg(OH)2 to Ba(OH)2.

A chemical reaction where calcium carbonate decomposes into calcium oxide and carbon dioxide gas when heated to a high temperature (1000°C). This reaction is endothermic, meaning it requires heat energy to occur.

A white solid compound that is prepared by passing carbon dioxide gas into lime water (calcium hydroxide solution). This reaction forms a precipitate of calcium carbonate.

The reaction between calcium chloride (CaCl2) and sodium carbonate (Na2CO3) in aqueous solution forms a precipitate of calcium carbonate and sodium chloride.

Plaster of Paris, also known as calcium sulfate hemihydrate (CaSO4.1/2H2O), is obtained by heating gypsum (calcium sulfate dihydrate, CaSO4.2H2O) at 120°C in a rotary kiln. This process partially dehydrates the gypsum.

If the temperature during the preparation of Plaster of Paris exceeds 140°C, further dehydration occurs, leading to anhydrous calcium sulfate (CaSO4). This form is known as dead burnt plaster and lacks the property of setting with water.

The setting of plaster of Paris involves two stages: setting and hardening. During the setting stage, hemihydrate crystals absorb water and form a paste. The hardening stage involves further hydration and crystallization, forming gypsum.

Gypsum (CaSO4.2H2O) is a white crystalline solid, sparingly soluble in water and dissolves in dilute acids. When strongly heated with carbon, it forms calcium sulfide.

Gypsum, when heated at different temperatures, undergoes transformations to form burnt plaster and ultimately lime (CaO).

Potassium carbonate (K2CO3) is more soluble than sodium bicarbonate (NaHCO3) in water. This means it doesn't precipitate out of solution when carbon dioxide (CO2) is added. The Solvay process relies on the precipitation of sodium bicarbonate, so it cannot be used to produce potassium carbonate.

Lithium (Li) is the least reactive alkali metal with water, despite having the highest heat of reaction. This is because its high melting point prevents it from melting quickly, thus limiting the surface area exposed to water. Reactivity increases down the group as the melting point decreases.

The reducing power of a metal depends on its standard electrode potential (E°). Lithium has the highest hydration enthalpy of all alkali metals, which contributes to a highly negative E° value. This means it readily releases electrons and acts as the strongest reducing agent in aqueous solution.

Lithium carbonate (Li2CO3) is a covalent compound, while sodium carbonate (Na2CO3) is ionic. Li2CO3 has a lower lattice energy than Na2CO3, meaning it requires less energy to break apart. This makes Li2CO3 more easily decomposed by heat. Na2CO3 is more stable.

Thermal stability refers to a compound's resistance to decomposition when heated. Metal carbonates decompose into metal oxides and carbon dioxide. Generally, the more ionic the carbonate, the more stable it is. Therefore, Na2CO3, being more ionic than other alkali metal carbonates, is the most thermally stable.

The process of heating calcium sulfate dihydrate (CaSO4.2H2O) to remove water molecules, resulting in the formation of calcium sulfate hemihydrate (2CaSO4.H2O) and eventually anhydrous calcium sulfate (CaSO4). This is the chemical reaction involved in the production of plaster of Paris.

Magnesium oxide (MgO) is formed when magnesium (Mg) reacts with oxygen (O2) in the presence of heat. This reaction results in a bright white light and is a common demonstration of a vigorous exothermic reaction.

Calcium silicate (CaSiO3) is formed when quick lime (CaO) reacts with silica (SiO2) in the presence of heat. This reaction is used in the production of cement and glass.

Calcium chloride (CaCl2) and calcium hypochlorite (Ca(OCl)2) are formed when chlorine (Cl2) reacts with slaked lime (Ca(OH)2). This reaction is used in the production of bleaching powder.

Calcium oxide (CaO) and nitrogen dioxide (NO2) are formed when calcium nitrate (Ca(NO3)2) is heated. This reaction is an example of thermal decomposition, where a single compound breaks down into two or more simpler compounds.

A mixture of minerals typically consisting of 50-60% calcium oxide (CaO), 20-25% silica (SiO2), 5-10% alumina (Al2O3), 1-3% magnesia (MgO), and smaller amounts of other components like iron oxide (Fe2O3) and sulfates. The specific proportions of these compounds determine the strength, setting time, and other properties of the cement.

Magnesium is crucial for the activity of numerous enzymes, particularly those involved in glycolysis. It is a central component of chlorophyll, the pigment responsible for photosynthesis in plants. Magnesium is also a cofactor in the breakdown of fats and glucose and plays a vital role in ATP synthesis. Furthermore, it contributes to the stability and synthesis of DNA and maintains electrolyte balance in the body.

Calcium plays a critical role in maintaining the anionic balance within plant vacuoles. It helps stabilize the permeability of cell membranes and is essential for the structure and function of proteins. Calcium is also vital for blood clotting.

Plaster of Paris is a white powder that is prepared by heating gypsum (CaSO4.2H2O) at 120°C. This process removes some of the water molecules from gypsum, leaving behind a hemihydrate formula (CaSO4)2.H2O. It's commonly used for making casts and molds.

When Plaster of Paris (CaSO4.H2O) is heated further at 200°C, it loses all its water molecules to form anhydrous calcium sulfate (CaSO4), also known as dead plaster. This form of calcium sulfate doesn't readily absorb water and loses its ability to set.

Milk of lime is a suspension of slaked lime (calcium hydroxide, Ca(OH)2) in water. It's a milky white liquid used in various applications like whitewashing, making mortar, and treating acidic soil.

Beryllium (Be) is an element that doesn't readily form hydrides by direct heating with dihydrogen. This is due to its high ionization enthalpy and small size, which make it difficult for beryllium to lose electrons and form a bond with hydrogen.

Soda ash refers to sodium carbonate (Na2CO3). It's a white, water-soluble solid and is one of the most important industrial chemicals. It's used in glass, detergent, and paper manufacturing.

The stability of metal carbonates increases as the electropositivity of the metal increases.

BeCO3 is least stable among alkaline earth metal carbonates due to the least electropositive nature of beryllium. It decomposes into BeO and CO2. To prevent decomposition, BeCO3 is kept in a CO2 atmosphere to shift the equilibrium towards the reactant side.

Ionization enthalpy decreases down a group in the periodic table due to increasing atomic size.

LiF has the lowest solubility in water among alkali metal fluorides because of its high lattice enthalpy. There's a stronger attraction between Li+ and F- ions due to their small size, making it difficult to break apart in water.

Amphoteric hydroxides react with both acids and bases. Be(OH)2 is a unique case because it reacts with NaOH to form beryllate ion, making it soluble in alkali solutions.

Smaller the size of an ion, higher is the lattice energy. LiF has more lattice energy than hydration energy leading to low solubility.

The stability of group 2 carbonates decreases down the group as the electropositive character of the metal increases.

The stability of metal carbonates increases as the electropositive character of the metal increases.