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NEET - Grade 11 - Chemistry - The s-Block Elements - Importance and Snapshot of S Block Element - Study ref# 677

Introduction: The  s-block elements of the periodic Table are those in which the last electron enters the outermost s-orbital. As the s-orbital can accommodate only two electrons, two groups [1 & 2] belong to the s-block of the Per... read more

NEET - Grade 11 - Chemistry - The s-Block Elements - Importance and Snapshot of S Block Element - Study ref# 678

Following sections must be covered to understand the S-block Elements: 1. Group 1 Elements: Alkali Metals 2. General Characteristics of the Compounds of the Alkali Metals 3. Anomalous Properties of Lithium 4. Some important Co... read more

NEET - Grade 11 - Chemistry - The s-Block Elements - Target Setup for S Block Element - Study ref# 679

Student requires to achieve the following milestones to get better grip over S-Block Element. The milestones / targets are as follows:-Starting Point: Days 0Test TypeAppear on TestTarget TestsScorePractice Test000%Chapter Test000%Subj... read more

NEET - Grade 11 - Chemistry - The s-Block Elements - Study ref# 1633

What are the common physical features of alkali metals? Answer: Physical Properties 1. Alkali metals are silvery white, soft and light metals. 2. Their densities are quite low (because of the large size). It increases on moving down the grou... read more

NEET - Grade 11 - Chemistry - The s-Block Elements - Study ref# 1634

What are the common chemical features of alkali metals? Answer: Alkali metals are highly reactive due to their low ionization enthalpy. Their reactivity increases down the group. 1. Reactivity towards air  The alkali metals tarnish in dry ai... read more

NEET - Grade 11 - Chemistry - The s-Block Elements - Study ref# 1635

Discuss the general characteristics and gradation in properties of alkaline earth metals. Answer: Elements of group-2, Be, Mg, Ca, Sr, Ba and Ra are collectively known as alkaline earth metals (except beryllium). General Characteristics A... read more

NEET - Grade 11 - Chemistry - The s-Block Elements - Study ref# 1636

Why are alkali metals not found in nature? Answer: Due to high chemical reactivity alkali metals do not occur free in nature. They are found in the earth’s crust in the form of halide, sulphate, carbonate, silicate, borate, oxide ores, etc. ... read more

NEET - Grade 11 - Chemistry - The s-Block Elements - Study ref# 1637

Explain why is sodium less reactive than potassium? Answer: The ionization enthalpy (∆iH1) of potassium (419 kJ mol-1) is less than that of sodium (496 kJ mol-1) and the standard electrode potential (E°) of potassium (- 2.925 V) is... read more

NEET - Grade 11 - Chemistry - The s-Block Elements - Study ref# 1638

In what ways lithium shows similarities to magnesium in its chemical behavior? Answer: Lithium resembles with magnesium due to their similar size [atomic radii, Li = 152 pm, Mg = 160 pm; ionic radii : Li+ = 76 pm, Mg2+ = 72 pm;] The impor... read more

NEET - Grade 11 - Chemistry - The s-Block Elements - Study ref# 1639

When an alkali metal dissolves in liquid ammonia, the solution can acquire different colours. Explain the reasons for this type of colour change. Answer: The dilute solutions of alkali metals in liquid ammonia exhibit dark colour because amm... read more

NEET - Grade 11 - Chemistry - The s-Block Elements - Study ref# 1640

Beryllium and magnesium do not give colour to flame whereas other alkaline earth metals do so. Why? Answer: Be and Mg atoms due to their small size and high effective nuclear charge bind their electrons more strongly. Therefore, they required ... read more

NEET - Grade 11 - Chemistry - The s-Block Elements - Study ref# 1641

Potassium carbonate cannot be prepared by Solvay process. Why? Answer: Potassium carbonate cannot be prepared by Solvay process because potassium bicarbonate being highly soluble in water would not be precipitated out. Hints: Potass... read more

NEET - Grade 11 - Chemistry - The s-Block Elements - Study ref# 1642

Starting with sodium chloride how would you proceed to prepare sodium metal? Answer: It is manufactured by electrolysis of a fused mixture of NaCl (40%) and CaCl2 (60%) in Down’s cell at 873 K. Na , liberated at the cathode is collected , in... read more

NEET - Grade 11 - Chemistry - The s-Block Elements - Study ref# 1643

Starting with sodium chloride how would you proceed to prepare sodium peroxide? Answer: It is obtained by heating sodium metal (which is obtained by the electrolysis of molten NaCl), in excess of air. The initially formed sodium oxide reacts... read more

NEET - Grade 11 - Chemistry - The s-Block Elements - Study ref# 1644

Starting with sodium chloride how would you proceed to prepare sodium carbonate? Answer: It is obtained by Solvay ammonia process. When CO2 is passed through a concentrated solution of brine (aqueous solution of NaCl) saturated with ammonia,... read more

NEET - Grade 11 - Chemistry - The s-Block Elements - Study ref# 1645

What happens when magnesium is burnt in air? Answer: 2Mg (s) + O2 (g) 2MgO(s) and 3 Mg(s) + N2(g) Mg3N2(s) Hints: Air contains nit... read more

NEET - Grade 11 - Chemistry - The s-Block Elements - Study ref# 1646

What happens when chloride reacts with slaked lime? Answer: It reacts with Cl2 to form calcium hypochlorite, Ca(OCl)2... read more

NEET - Grade 11 - Chemistry - The s-Block Elements - Study ref# 1647

What happens when calcium nitrate is heated? Answer: 2Ca(NO3)2 (s)  2CaO(s) + 4NO2(g) + O2(g) Hints: On heating, alkaline earth metal nitrate decompose into oxide with the evolution of NO2 and O2 gases. ... read more

NEET - Grade 11 - Chemistry - The s-Block Elements - Study ref# 1648

Describe the importance of limestone. Answer: Limestone 1. Calcium carbonate along with magnesium carbonate is used as a flux in the extraction of metals such as iron. 2. It is also used as an antacid, mild abrasive in toothpaste, a const... read more

NEET - Grade 11 - Chemistry - The s-Block Elements - Study ref# 1649

Describe the importance of cement. Answer: Cement 1. It is important building material. 2. It is used in concrete and reinforced concrete, in plastering and in the construction of bridges, dams and buildings.... read more

NEET - Grade 11 - Chemistry - The s-Block Elements - Study ref# 1650

Describe the importance of plaster of Paris. Answer: Plaster of Paris 1. It is extensively used in the building industry as well as plasters. 2. It is used in dentistry, in ornamental work and for making casts of statues and busts. 3.... read more

NEET - Grade 11 - Chemistry - The s-Block Elements - Study ref# 1651

Why is LiF almost insoluble in water whereas LiCl is soluble not only in water but also in acetone? Answer: LiF is almost insoluble in water due to its high lattice energy. But LiCl is soluble in water due to high hydration energy of Li+ ion... read more

NEET - Grade 11 - Chemistry - The s-Block Elements - Study ref# 1652

What happens when sodium metal is dropped in water? Answer: H2 gas is evolved which catches fire due to the liberation of extreme heat in the reaction.             2Na(s) + 2H2O(l) → 2NaOH (aq) + H2(g) Hints: Sodium being highly ... read more

NEET - Grade 11 - Chemistry - The s-Block Elements - Study ref# 1653

What happens when sodium peroxide dissolves in water? Answer: H2O2 is formed when sodium peroxide is dissolved in water.   Na2O2(s) + 2H2O(l) →2 NaOH(aq) + H2O2(l) Hints: Any true peroxide gives H2O2 when dissolves in water/ac... read more

NEET - Grade 11 - Chemistry - The s-Block Elements - Study ref# 1654

How do you account for the strong reducing power of lithium in aqueous solution? Answer: Electrode potential is a meas... read more

NEET - Grade 11 - Chemistry - The s-Block Elements - Study ref# 1655

Complete the following reactions, (i)                                   (ii)  Answer: (i) Peroxide ions react with water to form H2O2.                                      (ii) Superoxides ... read more

NEET - Grade 11 - Chemistry - The s-Block Elements - Study ref# 1656

Why are BeSO4 and MgSO4 readily soluble in water while CaSO4, SrSO4 and BaSO4 are insoluble? Answer: The lattice energy of alkaline earth metal sulphates is almost constant due to large size of sulphate ion. Thus, their solubility is deci... read more

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