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Baking soda is a mixture of : (a) Sodium carbonate and acetic acid (b) Sodium carbonate and tartaric acid (c) Sodium hydrogen carbonate and tartaric acid (d) Sodium hydrogen carbonate and acetic acid

Baking powder is a mixture of sodium hydrogen carbonate and a mild edible acid such as tartaric acid. Hence, the correct answer is option (c)... View Article

Convert propanoic acid into ethanoic acid?

Propanoic acid when reacts with an excess amount of ammonia gives propanamide. Propanamide on further reacting with bromine and potassium... View Article

Which of the following is not a simple tissue? (a)Parenchyma (b)collenchyma (c)xylem (d)sclerenchyma

Answer: (c) xylem Xylem is a complex tissue not a simple tissue. Xylem is a type of vascular tissue present in plants, which primarily... View Article

Pratyush took sulphur powder on a spatula and heated it. He collected the gas evolved by inverting a test tube over it, as shown in figure below. (a) What will be the action of gas on (i) dry litmus paper? (ii) moist litmus paper? (b) Write a balanced chemical equation for the reaction taking place.

(a) When sulphur is heated in the presence of air, sulphur dioxide SO2 is formed. (i) Sulphur dioxide is a neutral gas and thus there is no... View Article

The shape of ammonia molecules is: (A) Tetrahedral (B) Trigonal pyramid (C) Trigonal bipyramidal (D) Trigonal planar

Answer: (B) Trigonal pyramid The shape of the ammonia molecules is Trigonal pyramid or Distorted Tetrahedral. Also, read: Hybridization of Ammonia... View Article

What happens when limestone is heated strongly?

When limestone is heated strongly, we get quick lime i.e CaO CaCO3 ⇌ CaO (s) + CO2 (s) Calcium oxide can be produced by thermal... View Article

What is the hybridization of sulphur dioxide?

In sulphur dioxide, the hybridization that takes place is sp2 type. To determine this, we will first look at the sulphur atom which... View Article

Which among the following is not a base? (a) NaOH (b) KOH (c) NH₄OH (d) C₂H₅OH

Answer: (d) C2H5OH C2H5 OH is alcohol, not a base. An acid is any hydrogen-containing substance that is capable of donating a proton (hydrogen... View Article

The rate at which a substance reacts depends upon its: (A) Active mass (B) Atomic mass (C) Molecular mass (D) Equivalent mass

Answer: (A) Active mass The law of mass action states that the rate of a reaction is proportional to the product of the concentrations of each... View Article

Valency of oxygen is generally two whereas sulphur shows valency of two four and six. Explain.

Oxygen does not have vacant d-orbitals, so it cannot extend its valency beyond 2, but Sulphur shows valencies of 4 and 6 due to the presence of... View Article

The molar heat capacity of water at constant pressure p is 75 JK-1 mol-1. When 1.0 kJ of heat is supplied to 100 g of water which is free to expand, the increase in temperature of water is:

Molar heat capacity = 75 JK-1 mol-1 18g of water = 1 mole = 75 JK-1 mol-1 q=1kJ=1000J Heat, q = m.Cp.ΔT Number of moles = m =... View Article

Coal tar contains about -: (a) 300 substance (b) 400 substance (c)200 substance (d) 100 substance

Name the functional groups present in CH3CHO and CH3COCH3.

The functional groups present in: CH3CHO: −CHO Aldehyde CH3COCH3: −C− Ketone... View Article

Egg albumin in water forms : 1.true solution 2.colloid 3.suspension 4.none of these.

Answer: 2.colloid Egg albumin in water forms a colloidal solution. Also, read: Preparation of Colloidal solution of Egg Albumin... View Article

Carbonic anhydrase is found in: A.WBC B.RBC C.Blood plasma. D.All of the above

Answer: B. RBC Carbonic anhydrase is found in red blood cells. The carbonic anhydrase enzymes work to catalyze the conversion of carbon dioxide... View Article

Name any 10 metals and any 10 nonmetals.

The name of 10 metals and 10 non-metals are given below in the table: 10 Metals 10 Non-metals Lithium (Li) Hydrogen... View Article

In a periodic table the average atomic mass of magnesium is given as 24.312 u. The average value is based on their relative natural abundance on earth. The three isotopes and their masses are 12 24Mg(23.98504u), 12 25 Mg (24.98584u) and 12 26 Mg (25.98259u). The natural abundance of 12 24 Mg is 78.99% by mass. Calculate the abundances of other two isotopes.

Let the abundance of 12Mg24 is x% Now, abundance of 12Mg26 by mass = (100−78.99−x)% = (21.01−x)% Therefore, as per... View Article

M	T	W	T	F	S	S
	1	2	3	4	5	6
7	8	9	10	11	12	13
14	15	16	17	18	19	20
21	22	23	24	25	26	27
28	29	30