Advertisements
Advertisements
प्रश्न
What is variable valency? Name two elements having variable valency and state their valencies.
उत्तर
Variable valency: Some elements exhibit more than one valency. They are said to have variable valency, e.g. Iron, copper, tin, lead.
Iron Fe Fe2+ or Fe3+
Copper cu cu+ or cu2+
APPEARS IN
संबंधित प्रश्न
Explain the Mass number with example.
Multiple Choice Questions
If the atomic number of an atom is 17 and mass number is 35 then number of neutron will be
Draw the atomic diagram of the following element showing the distribution of – protons, neutrons and the electrons in the various shell of the atom.
Argon – \[\ce{^40_18Ar}\]
[The upper number represent the – mass number and the lower number represent the – atomic number e.g. calcium – mass number = 40, atomic number = 20]
The diagram represents an isotope of hydrogen [H]. Answer the following:
Atomic no. = 1
Mass no. = 1
Do isotopes have the same atomic number or the same mass number?
The diagram represents an isotope of hydrogen [H]. Answer the following:
Atomic no. = 1
Mass no. = 1
If an isotope of ‘H’ has mass no. = 3, how many neutrons does it have.
Draw the structure of the following atoms showing the nucleus containing – protons, neutrons and the orbits with the respective electron:
Isotopes of hydrogen [11H, 21H, 31H]
An element ‘A’ has mass number 23 and atomic number 11. State the –
- no. of neutrons in its shell,
- electronic configuration of the element ‘A’.
Which of the following are true for an element?
- Atomic number = number of protons + number of electrons
- Mass number = number of protons + number of neutrons
- Atomic mass = number of protons = number of neutrons
- Atomic number = number of protons = number of electrons
The particles that make up the atom are called ______ particles.
In which one of the following, the number of protons is greater than the number of neutrons but number of protons is less than the number of electrons?
