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AS Level Chemistry help - atomic structure

Hi, I am having some trouble with some of these questions, can someone please help me?

Thanks!

1. What is the difference between an element and an isotope? (2 marks)

2. Name the main particles found in the atomic nuclei of all elements, with the exception of an isotope of one particular element. Give the main characteristics of these particles and name the exceptional isotope.

Names and characteristics (4 marks) -

Exception (1 mark) -


3. State whether the first ionisation energy is endothermic or exothermic and explain your choice (3 marks).

Thanks for your time and help!
1) :eek:

2) This is easy- neutrons and protons(you probably know the characteristics!!). Hydrogen(Z=1) is the exception as it has no neutrons

3) I think its endothermic as we need to supply energy in order to remove the electrons
Reply 2
Thanks for your reply, I greatly appreciate your help.

Could you please tell me the answer to no.1? I got an idea what the answer is, but I dunno how to phrase it! :redface:

Thanks. :smile:
arsenalfan.

I got an idea what the answer is, but I dunno how to phrase it!


Yeah I understand. I guess you could write something like isotopes are atoms of the same element, with a different number of neutrons. For example, Chlorine has two isotopes, Cl-35 and Cl-37. Cl-35 has 18 neutrons, however Cl-37 has 20 neutrons.
I dont think I've answered it too well, sorry
Reply 4
Q1 - an element is a substance that cannot be broken down into any simpler substances. An isotope of an element has the same number of protons but a different number of neutrons. e.g. elemental hydrogen (protium) has 1p0n, deuterium isotope has 1p1n and tritium isotope has 1p3n. Therefore the difference is the number of electrons

Q2 - Exception is the protium isotope. Protons are present, have a mass of 1 and a charge of 1+. Neutrons are present and have a mass of 1 and no charge.

Q3 - Endothermic - IE is the energy required to free an electron i.e. the energy that has to be put in.

Hope that helps!

Michael
Should you know this from GCSE? Isotope so.
stratomaster
Should you know this from GCSE? Isotope so.



:rolleyes: cheesy but i like it lol
Reply 7
What is the difference between an element and an isotope? (2 marks)
An isotope has the same number of protons but a different number of neutrons whereas a element is simplay substance


2. Name the main particles found in the atomic nuclei of all elements, with the exception of an isotope of one particular element. Give the main characteristics of these particles and name the exceptional isotope.
Protons
Neutrons
Electrons
Reply 8
Thanks for all replies! I got all questions solved now! :biggrin:

Cheers. :smile:
Reply 9
Elements differ between themselves by the number of protones. Isotopes of same lement have equal number of protons but different number of neutrons. For proper definitins I would advice google.
Reply 10
arsenalfan.
Hi, I am having some trouble with some of these questions, can someone please help me?

Thanks!

1. What is the difference between an element and an isotope? (2 marks)

2. Name the main particles found in the atomic nuclei of all elements, with the exception of an isotope of one particular element. Give the main characteristics of these particles and name the exceptional isotope.

Names and characteristics (4 marks) -

Exception (1 mark) -


3. State whether the first ionisation energy is endothermic or exothermic and explain your choice (3 marks).

Thanks for your time and help!

Looks like your homework ^o)
Reply 11
belis
Elements differ between themselves by the number of protones. Isotopes of same lement have equal number of protons but different number of neutrons. For proper definitins I would advice google.


Thx for ur reply.
Googly
Looks like your homework ^o)


Yea, i did the hw, then the questions I was stuck on, I asked on TSR. :smile: