AS Module 1 – Flashcards
Unlock all answers in this set
Unlock answersquestion
What is the Relative Atomic Mass (Ar)? |
answer
The average mass of an atom of an element compared to 1/12 of the mass of an atom of carbon-12 |
question
What is the Molar Mass? |
answer
The mass in grams of one mole of particles (The top number on Periodic Table) |
question
What is a Mole? |
answer
The measure of the number of particles |
question
What is the Empirical Formula? |
answer
The simplest ratio of atoms of each element in a compound |
question
What is the Molecular Formula? |
answer
The actual number of atoms of each element in a molecule |
question
What is the Relative Mass and Relative charge of a Proton? |
answer
Relative Mass: 1 Relative Charge: +1 |
question
What is the Relative Mass and Relative Charge of a Neutron? |
answer
Relative Mass: 1 Relative Charge: 0 |
question
What is the Relative Mass and Relative Charge of an Electron? |
answer
Relative Mass: 1/1800 Relative Charge: -1 |
question
What is the Mass Number? |
answer
The number of protons and neutrons in the nucleus of an element (A) |
question
What is the Atomic Number? |
answer
The number of protons in the nucleus (Z) |
question
What is an isotope of an element? (Physical and Chemical properties?) |
answer
Has the same number of protons BUT a different number of neutrons Physical properties of isotopes differ Chemical properties of isotopes are the same |
question
Name the 4 stages of Mass Spectrometry |
answer
1) Ionisation |
question
Describe the process of ionisation |
answer
Electrons from the electron gun is fired into the sample and knocks off the outermost electon forming a unipositive ion |
question
What is the general equation for ionisation? |
answer
X(g) → X+(g) + e- |
question
How does acceleration occur in mass spectrometry? |
answer
A negative electric field accelerates the beam of postive ions and slits narrow it |
question
Describe how deflection occurs |
answer
The fast moving beam of positive ions is deflectd by variable magnetic field |
question
For a given magnetic field: the greater the mass... |
answer
the less the ions are deflected |
question
For a given magnetic field: the greater the postive charge... |
answer
the more they are deflected |
question
Describe the process of detection |
answer
When a positive ion reaches the detecter, a tiny current is produced. The signal is fed to a recorder. |
question
Why do the chemical properties of isotopes stay the same? |
answer
Because there are the same number of electrons and electron configuration |
question
Recite the electronic configuration pattern |
answer
1s2 2s2 2p6 3s2 3p6 3d10 4s2 4p6 4d10 4f14 |
question
As you go down Group II from beryllium to barium... |
answer
there is a succesive decrease in first ionisation energy |
question
There is a decrease in ionisation energy as you go down Group II because.... |
answer
The outer electron is: - more shielded from nuclues by inner electrons SO electron is more easily removed |
question
As you go across Period 3... |
answer
there is a general increase in ionisation energy |
question
There is a general increase in ionisation energy as you go across Period 3 because... |
answer
the nuclear charge in each element increases and so the electrons are attracted more strongly and it takes more energy to remove |
question
There is a fall in ionisation energy from magnesium to aluminium because... |
answer
the outer electron in aluminium is in a p sublevel (higher energy level than s sublevel of magnesium) |
question
The fall in ionisation energy from Phosphorus to Sulphur is because... |
answer
the electrons are paired in the 3p sub level of Sulphur. This means they repel each other and are less attracted to the nucleus. |
question
What is a covalent bond? |
answer
The bond formed between two non-metals (they share electrons) |
question
What is ionic bonding? |
answer
The bond formed between a positive metal and a negative non-metal (transferring of electrons) |
question
What is Avogadro's Constant (L)? |
answer
6.023 x 1023 |
question
How many particles does 1 mole of a substance contain? |
answer
6.023 x 1023 (Avogadro's Constant) |
question
What is the equation for the Number of moles?< |
answer
Mass (g) Molar Mass (gmol-1)
|
question
What is the Ideal Gas Equation? |
answer
PV = nRT P = Pressure in Pa T = temperature in K |