Basic Structure of an Atom
Identify this symbol Ar
Argon
An unbalanced chemical reaction shows violation of of which law?
Law of conservation of Mass.
What is the atomic mass of He?
4 u
Define the valency of an Atom.
Valency is the combining capacity of an atom.
What will be the electronic configuration of Magnesium?
k,L,M
2,8,2
In a reaction 5.3 gm of sodium carbonate is reacted with 6 gm of ethanoic acid. The products were 2.2 gm of carbon dioxide, 0.9 gm of water and 8.2 gm of sodium ethanoic. Are these observations in accordance with the Law of Conservation of Mass?
5.3 gm + 6gm = 2.2gm +0.9 gm + 8.2 gm
11 .3 gm = 11.3 gm
Yes.
The molecular mass of NaCl is 58.5 gm. True/False
False.
State the valency of Hydrogen, Magnesium and Aluminium?
+1, +2 and +3
What is the Atomic Mass of Ca?
40
Why there is no change in mass during a Chemical Reaction?
Law of Conservation of Mass- Mass can neither be created nor be destroyed in a Chemical Reaction.
The Molar Mass of AlCl3 will be:
133.5 gm
The valency of Calcium is 2 more than the valency of Helium. True/ False?
True
Valency of Calcium is +2 while that of Helium is zero.
Find the number of neutrons present in an atom of Sodium.
Atomic Mass = 23
Atomic Number = 11
No. of Protons= 23-11= 12
Hydrogen and oxygen combine in the ratio 1:8 by mass to form water. What mass of oxygen gas is required to react completely with 3 gm of hydrogen gas?
24 gm
The Molecular Mass of Mg(OH)2 will be:
58 u
What will be Chemical Formula Of Potassium Chloride?
KCl
Name the element having 0 neutrons.
Hydrogen.
Nitrogen and hydrogen combine in the ratio 14:3 by mass to form 1 mole of Ammonia. If 42.5 gm of ammonia is produced in a reaction then how much amount of nitrogen is used in this reaction?
35 gm
The Molar Mass of Nitrogen gas is 14 gm. Trues / false?
False, it will be 28 gms as Nitrogen gas stands for N2.
Is it a correct representation of a Chemical Formula: ONa2
Why or why not?
No, because Cation is written first and anion is written later.