Tag: chemistry

Quizzes (490) Questions (9892)

Questions Related to chemistry

Multiple choice chemistry structure of the atom neutrons discovery of neutrons structure of atoms

The order (lowest to highest) of e/m (charge/mass) ratio for electron (e), proton (p), neutron (n) and alpha particle $(\alpha)$ is:

  1. $e, p, n, \alpha$
  2. $n, p, e, \alpha$
  3. $n, p, \alpha, e$
  4. $n, \alpha, p, e$
Reveal answer Fill a bubble to check yourself
D Correct answer
Explanation
The increasing order (lowest to highest) of e/m (charge/mass) ratio is $ n < \alpha < p < e$.Neutron being neutral has zero charge and lowest e/m ratio. An electron has a unit charge but negligible mass. Hence, the electron has maximum e/m ratio.For an alpha particle, the e/m ratio is 2/4 or 0.5.For proton, e/m ratio is 1/1 or 1.


Multiple choice chemistry structure of the atom neutrons discovery of neutrons structure of atoms

Which of the following doesn't have charge?

  1. Proton

  2. Neutron

  3. Electron

  4. Isotope

  5. Ion
Reveal answer Fill a bubble to check yourself
B Correct answer
Explanation

Neutron has zero unit charge.
The neutron is a subatomic particle, symbol n or $n^0$, with no net electric charge and a mass slightly larger than that of a proton. Protons and neutrons, each with mass approximately one atomic mass unit, constitute the nucleus of an atom, and they are collectively referred to as nucleons

Multiple choice chemistry structure of the atom neutrons discovery of neutrons structure of atoms

 Which of the following would not be attracted or deflected while traveling through an electric field?
I. Gamma ray
II. Beta particle
III. neutron.

  1. i only

  2. ii only

  3. i and ii Only

  4. i and iii only
Reveal answer Fill a bubble to check yourself
D Correct answer
Explanation

Gamma rays and neutrons have no charge as they are neutral, hence, these would not be attracted or deflected while traveling through an electric field.

Multiple choice chemistry structure of the atom neutrons discovery of neutrons structure of atoms

Doubly magic nucleus is:

  1. $ _{ 82 }^{ 207 }{ Pb }$
  2. $ _{ 82 }^{ 206 }{ Pb }$
  3. $ _{ 82 }^{ 208 }{ Pb }$
  4. $ _{ 83 }^{ 209 }{ Bi }$
Reveal answer Fill a bubble to check yourself
C Correct answer
Explanation

Doubly magic nucleus is $\displaystyle _{ 82 }^{ 208 }{ Pb }$. It has 82 protons and $\displaystyle 208-82=126$ neutrons. 82 and 126 are magic numbers.

Multiple choice chemistry pure substances and mixtures: separation of mixtures dry methods of separation process of separating components of a mixture method of separation

The constituents of a heterogeneous mixture are X, Y and Z. 
If mixture of X and Y taken separately then, X can be separated using magnetic separation from Y. If mixture Y and Z is taken then it can be separated using distillation method.

Which of the following mixture can be X, Y, Z?

  1. Iron, salt, water.

  2. Sulphur, carbon disulphide, water.

  3. Gun powder, common salt, water.

  4. Iodine, sand, alcohol.
Reveal answer Fill a bubble to check yourself
A Correct answer
Explanation

Iron (X) is magnetic and can be separated from salt (Y). Salt (Y) and water (Z) form a solution that can be separated by distillation. This matches the description.

Multiple choice chemistry mix and separate dry methods of separation process of separating components of a mixture method of separation

State a method to separate ammonium chloride from a mixture of ammonium chloride and potassium chloride.

  1. Sedimentation

  2. Sublimation

  3. Magnetic separation

  4. Solvent extraction
Reveal answer Fill a bubble to check yourself
B Correct answer
Explanation

Ammonium chloride sublimes on heating therefore it is easy to remove it by sublimation from a mixture of ammonium chloride and potassium chloride.

Multiple choice chemistry mix and separate dry methods of separation process of separating components of a mixture method of separation

Which method can be used to separate two solid mixtures one of which dissolves in a particular solvent and other does not?

  1. Separating funnel

  2. Sublimation

  3. Magnetic separation

  4. Solvent extraction
Reveal answer Fill a bubble to check yourself
D Correct answer
Explanation

The two solid mixtures, one of which dissolves in a particular solvent and other does not, can be separated by solvent extraction method.