Chemistry Test - 1

In the year of 1909, Millikan gave an experiment which is known by the name oil drop experiment. In this experiment, a simple apparatus is used in which actions of all forces i.e., electric, gravitation and air drag forces balance each other and this is used to determine the electric charge present on many of the droplets in an oil mist. The force on any electric charge in an electric field is given by the product of the charge and the electric field.

Charge carried by the oil drop =1.282×10⁻¹⁸c

Charge of electron =1.6022×10^−19C

∴ Electrons present on the oil drop carrying 1.282×10⁻¹⁸C charge

Thus, the number of electrons on the surface is 8.0.

Hence, the correct answer is 8.0.

The Lassaigne test is performed when we need to confirm the presence of nitrogen and sulfur in an organic compound.

The test is performed as follows:

A piece of sodium metal is taken into a fusion tube and melted. A little of the sample is added to the fusion tube. It is then heated strongly until red hot. The red hot tube is then broken into a china dish and distilled water is added to it. The solution is then boiled and filtered. This is called the sodium standard errors. The extract is then divided into two parts; In one part NaOH is added to make it alkaline. Alkaline Sodium extract is then boiled with a freshly prepared Ferrous sulfate solution. The solution is then cooled and acidified with a dilute sulphuric acid solution. A blood-red colour indicates the presence of both Nitrogen and sulfur.

The reaction that takes place is:

The complex ferric sulphocyanide gives blood red color to the solution.

Thus, the complex formed when both sulfur and nitrogen are present in an organic compound is Fe(SCN)₃.

From Arrhenius equation, we obtain:

We are familiar with the colligative properties of the compounds from the physical chemistry concept and also terms and definitions relating to it.

Now, let us see the meaning of the depression in freezing point and how it is calculated.

Depression in freezing point is the decrease in the freezing point of the solvent when a non-volatile solute is added to it or in simple words it can be said that the freezing point of a solution is less than that of the freezing point of the pure solvent. Temperature plays an important role here.

Now, let us calculate the above-given question according to which the data are given as,

Mass of the solute (non-electrolyte) = W = 1 g

Mass of the solvent that is W = 50g

Substituting the values, we can get the value of the molar mass of solute.

Thus, the answer is 256 g/mol which is the molar mass of the solute.

Hence, the correct answer is 256.

In this question, we are given all the required values of the terms which are required for us to get to our solution, so let's start solving; First, we will calculate the value of change in pressure and volume (ΔPV) as the direct value is not given, for this, we will use the given two values of pressure and volume.

Now let's put all the values in the mentioned formula,

Therefore, the change in enthalpy of the system after the non-ideal gas changes its states is 44.

Hence, the correct answer is 44.

Benzene doesn't undergo nucleophilic substitution reaction easily but as the number of NO₂₋ (electron-withdrawing group) group increases, benzene become electron-deficient and it undergoes nucleophilic substitution.

When −NO₂ present at ortho and para to chlorine then nucleophilic substitution occurs.

So, 2,4,6 - trinitro chlorobenzene reacts with NaOH and perform nucleophilic substitution reaction.

Aniline reacts with a mixture of sodium nitrite and hydrochloric acid and forms benzene diazonium chloride. The structure of Benzene diazonium chloride is

Benzene diazonium chloride reacts with aniline in presence of dilute hydrochloric acid and undergoes coupling reaction and produces stable azo products. In this reaction, benzene diazonium chloride acts as an electrophile in coupling with activated aniline. In this type of reaction, substitution takes place at the para position. So, the reaction of Benzene diazonium chloride with aniline in presence of dilute hydrochloric acid is as follows:

Determine the group and period number of all given elements.

Out of the elements given to us, element bismuth is present on the right side of the periodic table in the sixth period and while other elements (Phosphorous, sulphur, Chlorine) are present in the third period of the periodic table. Now, using the position of elements in the periodic table we can determine the increasing order of electronegativity as follows:

As per the trend of electronegativity, electronegativity increases moving from left to right, across the period and decreases moving down the group, from top to bottom. Hence the element presents down in the group will have less electronegativity and if elements are present in the same period then the element present to the right side of the periodic table will have more electronegativity.

Here, Bismuth is present in V A group and sixth period whereas other elements are placed at the top of the periodic table in the third period of the periodic table. Thus, bismuth will have at least electronegativity than other elements due to its position in the periodic table.

Now, elements phosphorus, sulphur and chlorine are placed in the same period but different groups according to the position of elements in periodic table chlorine is placed to the extreme right in the periodic table among the rest 3 elements hence chlorine will have the highest electronegativity before chlorine sulphur is placed hence it will have the second-largest electronegativity and at the third position will be phosphorous.

Thus, the increasing order of electronegativity in element follows the order as follows: Bismuth < Phosphorus < Sulphur < Chlorine or 

Deuteron, the nucleus of deuterium (heavy hydrogen) that consists of one proton and one neutron. Deuterons are formed chiefly by ionizing deuterium (stripping the single electron away from the atom). It is used as projectiles to produce nuclear reactions after accumulating high energies in particle accelerators.

Thus, deuteron is not a subatomic particle.

There are two types of H bond and they are as follows:

1. Intramolecular hydrogen bond: It is formed when a hydrogen atom is in between the two highly electronegative (F, O, N) atoms present within the same molecule. For example, in o-nitrophenol, hydrogen is in between the two oxygen atoms.

2. Intermolecular hydrogen bond:- It is formed between two different molecules of the same or different compounds. For example, H-bond in case of HF molecule, alcohol or water molecules, etc.