Tuesday, July 31, 2018

Basic question of chemistry

!.In a solution of saltwater (a saline solution), salt is the:
  A.solute
  B.solvent
  C.Colloid
  D.Sol



Answer: Solute
Salt is the solute because it dissolves in the solvent (water). In a mixture of two fluids, the solute is present in lesser quantity compared with the solvent.

2. All of the following elements are liquids around room temperature except which one?
   A.Gallium
   B.Bromine
   C.Magnesium
   D.Murcury





Answer: Mercury
Bromine and mercury are liquid at room temperature. You can melt gallium in the palm of your hand. If you put pure magnesium in your hand, it may react with the water in your skin and ignite, but it won't melt.

3.All of the following are amino acids except:
   A.Tryptophan
   B.Leucine
   C.Adenine
   D.Tyrosine




Answer:Adenine
Adenine is a nucleic acid and not an amino acid.
































Monday, July 30, 2018

Acid Base question



1.Soap is
   A.acidic
   B.alkaline
  C.neutral
  D.basic

Answer:B

2.Amphoteric oxides include
   A.SO2
   B.ZnO
   C.P2O5
   D.P4O10

Answer:B

3.When an acid (H+) is added to alkali (OH-), the product is
   A.hydroxides
   B.water
   C.salts
   D.hydrogen gas

Answer;C

4.Acids are
   A.corrosive
   B.turn litmus from blue to red
   C.sour in taste
   D.all of these

Answer;D

5.Distinction between a weak acid or strong acid can be made through
   A.litmus indicator
   B.universal indicator
   C..methyl orange indicator
   D.Phenolphthalein indicators

Answer;B

Saturday, July 28, 2018

Basic question of chemistry for 11th and 12th students





1.Question: The most abundant rare gas in the atmosphere is
a.He
b.Ne
c.Ar
d.Xe

Answer:-Argon is the inert gas. It is the most abundant rare gas in the atmosphere because it occurs in the earth crust with 93%.
It is a not reactive element. So for this questions Ar is the correct.

other related question;-

2.Equal masses of oxygen, hydrogen and methane are kept under identical condition.The ratio of the volumes of gasses will be
A. 2 : 16 : 2
B. 2 : 16 : 1
C. 1 : 16 : 2
D. 1 : 1 : 1

Answer ;-C
Convert the mass into moles (use the formula n=m/Mr)
m = mass and Mr = Molecular weights
Molecular weights are 32(Oxygen), 2(Hydrogen), and 16(Methane), respectively.
Since the masses are equal, you can take the mass as x. So, the number of moles would be:
n(O2) = x/32
n(H2) = x/2
n(CH4) = x/16
The ratio of their volumes is (O2) : (H2) : (CH4) = 1 : 16 : 2