OCR GCE Chemistry - Atoms and Reactions

What are the 4 stage of scientific process?

-Observation

-Theory/model

-Hypothesis

-Tests

 

Why are laboratories used in controlled experiments?

-Control variables

 

What are the 3 types of particle atoms are made of?

-Protons, neutrons and electrons

 

What do electrons whizz around in?

-Orbitals

 

Where is most of the mass of the atom concentrated?

-Nucleus

 

Where is most of the space of the atom found?

-Orbitals

 

Why is relative mass and relative charge for subatomic particles?

-They are so small

 

What is the word used to describe the mass of an electron. What is its actual mass?

-Negligible

-1/2000

 

What is the mass of 2 nucleons?

-+2

 

What is the charge of a nucleus of an atom?

-+1

 

What is the charge of a whole atom?

-0

 

What charge will an atom have it loses 3 electrons?

-+3

 

What property is represented by the letter A for an atom?

-Mass (nucleon) number

 

What letter is used to show the Atomic (proton) number of an element?

-Z

 

Lithium has 7 nucleons and 3 protons. How many neutrons and electrons does it have?

-4 neutrons and 3 electrons

 

If an element has different numbers of protons and electrons, what is it called?

-Ion

 

Negative ions have **** electrons than protons

-More

 

Positive ions have more ******* than electrons

-Protons

 

What is an isotope?

-Atom of the same element with different numbers of neutrons but same number of protons

 

What decides the chemical properties of an element?

-Number and arrangement of electrons

 

Why do isotopes have the same chemical properties as its own element?

-Same electron configuration

 

What may differ about isotopes of an element? Give examples

-Physical properties

-Densities, rates of diffusion

 

Why do the physical properties of an isotope differ?

-Physical properties depend more on the mass of the atom

 

What is the name given to what we think an atom looks like now?

-Accepted model

 

Why is the accepted model assumed as true?

-Fits all the observations and evidence so far, until someone shows that it’s incomplete or wrong

 

Where did the word ‘ATOM’ originate from? What does it mean?

-‘Atomos’ in Greek

-Uncuttable

 

What did the Ancients Greeks and John Dalton in 19^th century think about atoms?

-They were indivisible particles (solid spheres), with different spheres for different elements

 

Who concluded in 1897 that atoms were not just solid spheres?

-JJ Thompson

 

 

How did JJ Thompson prove that atoms were not just solid spheres?

-His measurements of charge and mass showed that an atom must contain even smaller, negatively charged  particles.

 

What did JJ Thompson call the negatively charged particles? What do we call them now?

-Corpuscles

-Electrons

 

What was JJ Thompson’s new model of an atom described as?

-Plum pudding model

 

Briefly describe JJ Thompson’s plum pudding model

-Positively charged sphere with negative electrons embedded…