The Periodic Table

Question 1

What is an element?

Answer 1

A substance that cannot be split into simpler substances by chemical means.

Question 2

What is a triad?( Dobereiner’s triads)

Answer 2

A group of three elements with similar chemical properties in which the atomic weight(relative atomic mass) of the middle element is approximately equal to the average of the other two.

Question 3

What are Newland’s octaves?

Answer 3

Arrangements of elements in which the first and the eighth element, counting form a particular element, have similar properties.

Question 4

What is Mendeleev’s Periodic Law?

Answer 4

When elements are arranged in order of increasing atomic weight(relative atomic mass) the properties of the elements recur periodically, i.e the properties displayed by an element are repeated at regular intervals in other elements.

Question 5

Why did Mendeleev reverse the order of some elements?

Answer 5

So that they are arranged in groups with similar properties

Question 6

What is the atomic number

Answer 6

The number of protons in the nucleus of an atom

Question 7

Who discovered that elements should be arranged in terms of increasing atomic number?

Answer 7

Henry Moseley

Question 8

What is the modern periodic table?

Answer 8

Arrangement of elements in increasing atomic number.

Question 9

What is the modern periodic law?

Answer 9

When elements are arranged in order of increasing atomic number, the properties of the elements recur periodically, i.e the properties displayed by an element are repeated at regular intervals in other elements

Question 10

What is the mass number of an element?

Answer 10

Number of protons and neutrons in the nucleus of an atom

Question 11

What is an isotope?

Answer 11

Atoms of the same element( they have the same atomic number) which have different mass numbers due to the different number of neutrons in the nucleus.

Question 12

What is relative atomic mass?

Answer 12

The average mass numbers of the isotopes of the element as they occur naturally taking their abundances into account, based on 1/12th of the carbon-12 atom.

Question 13

What are the stages of a mass spectrometer?

Answer 13

Victor is always sitting down
1. Vaporisation
2. Ionisation
3. Acceleration
4. Separation
5. Detection

Question 14

What is the principle of mass spectrometry?

Answer 14

Charged particles moving in a magnetic field are deflected to different extents according to their masses and are thus separated according to these masses

Question 15

What is an electron configuration?

Answer 15

Shows the arrangement of electrons in an atom of an element.

Question 16

What is the Aufbau principle?

Answer 16

When building up to the electron configuration of an atom in its ground state, the electrons occupy the lowest available energy levels

Question 17

What is Hund’s Rule of Maximum Multiplicity?

Answer 17

When two or more orbitals of equal energy are available the electrons occupy then singly before filling them in pairs.

Question 18

What is the Pauli Exclusion Principle?

Answer 18

No more than two electrons may occupy an orbital and they just have opposite spin