Chemistry - Online Test
Q1. Rutherford’s α–particle scattering experiment supported the discovery of
Answer : Option D
Explaination / Solution:
Rutherford's model of an atom : Ernest Rutherford was interested in knowing how the electrons are arranged within an atom. Rutherford designed an experiment for this. In this experiment, fast moving alpha (α)-particles were made to fall on a thin gold foil.
On the basis of his experiment, Rutherford put forward the model of an atom, which had the following features:
- There is a positively charged centre in an atom called the nucleus.
- Nearly all the mass of an atom resides in the nucleus. The electrons revolve around the nucleus in well-defined orbits.
- The size of the nucleus is very small as compared to the size of the atom.
Q2. Stratosphere is a region of the atmosphere which contains :
Answer : Option C
Explaination / Solution:
Stratosphere, which is the second layer of atmosphere, contains ozone layer that absorbs UV-radiation from sun's rays.
Q3. Which among the following is not considered as a part of transition elements?
Answer : Option A
Explaination / Solution:
Zn, Cd and Hg are not considered as transition elements because they donot have incompletely filled d orbital in its ground state or stable oxidation state.
Q4. CH3 CH(OCH3 )CHO is called
Answer : Option C
Explaination / Solution:
This is Methoxypropionaldehyde or 2 – Methoxypropanal
Q5. The giant planets Jupiter and Saturn consist mostly of
Answer : Option B
Explaination / Solution:
The name ‘gas giant’ was coined in 1952 by science fiction writer James Blish to refer to all the giant planets. The giant planets (Jupiter and Saturn) are huge gas balls, which is quite different than Earth and and other three rocky inner planets. Gas giants are primarily composed of gases, such as hydrogen and helium, and a much thicker layer of metallic hydrogen, along with a molten rocky core.
Unlike rocky planets, gas giants do not have a well-defined surface, and there is no clear boundary between where the atmosphere ends and the surface begins. In other words, you wouldn’t be able to land on these planets, as their atmospheres simply become gradually denser towards the core, perhaps with liquid or liquid-like states somewhere in between.
Q6. The oxidation number of Fe in K4[Fe(CN)6] is
Answer : Option B
Explaination / Solution:
CN has charge of –1 charge.
Q7. Norethindrone is a
Answer : Option C
Explaination / Solution:
Norethindrone is synthetic infertility drug.
Q8. standard hydrogen electrode operated under standard conditions of 1 atm H2 pressure, 25°C, and pH = 0 has a cell potential of
Answer : Option A
Explaination / Solution:
Standard electrode potential of hydrogen electrode is taken as 0V.
Q9.
The formation of the Cl2 molecule can be understood in terms of the sharing of a pair of electrons between the two chlorine atoms, each chlorine atom contributing one electron to the shared pair. Choose the most appropriate name of the bond that is formed
Answer : Option D
Explaination / Solution:
Two chlorine atoms will each share one electron to get a full outer shell and form a stable Cl2 molecule.
By sharing the two electrons where the shells touch each chlorine atom can count 8 electrons in its outer shell. These full outer shells with their shared electrons are now stable and the Cl2 molecule will not react further with other chlorine atoms. One pair of shared electrons form a single covalent bond.
Q10. Sodium and potassium belong to the category of
Answer : Option B
Explaination / Solution:
Na and K are shiny, soft ,highly reactive metal at standard temprature and pressure and electronic configaration of Na & K is ns2,,compounds of Na & K are available most aboundenty in nature so thees two are alkali metal.
