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Flave
Sep25-06, 02:05 PM
Hi, I'm new and I was wondering if anyone could help me with this

An atom of argon

37
Ar
18

is ionised by the removal of 2 orbiting electons.
In the ion there will be..

a) ______ protons and ______ neutrons

b) So what is the charge in C of this ion?

__
note, having tried this I got 18 protons and 18 neutrons but have no clue about b and I'm not sure if a is true.
Thankyou if anyone can assist me, I'd be very greatful indeed.

Chi Meson
Sep25-06, 03:30 PM
18 + 18 = 36. But the number above the symbol is 37. So, 18 protons plus how many neutrons will give you 37 "nucleons"?

No clue about b? How many electrons are missing? (2) . What the charge of each electron?

Flave
Sep25-06, 03:44 PM
19 neutrons? thanks.

Also, for b would it be double the charge of an electron?
2 x 1.6x10^-19?

Also, can I ask what a constituent particle is?
it says ask for one for this ion that has
a zero charge per unit mass ration
and the largest charge per unit mass ratio.

Chi Meson
Sep25-06, 04:12 PM
2 x "e" that's correct. You might need to specify that the net charge is positive, since the ion is missing electrons.

As for the second part: talk about an obtuse way of stating the question. "Constituent particle" is referring to the three fundamental particles that make up atoms (electron protons and neutrons).

The question asks: "Which particle has no net charge (regardless of it's mass), and which particle has least mass."

Flave
Sep26-06, 01:04 AM
thankyou very much for your help. :)

I have another problem that is troubling me in this paper
A

239
92 U

nucleus may decay by emitting to beta- particles to form a plutonium nucleus.

X
Y P

State what Xand Y represent and their values.

Well I think that X would be the number of nucleons and Y the number of protons but I'm puzzled as to how I'd solve it.

Chi Meson
Sep26-06, 05:35 PM
Do you know what happens in "beta decay"? OK I'll tell you. A neutron "changes into" (the whole story is advanced and more complicated) a proton and ejects a high-speed electron (that's the beta particle). Does the X number change? HOw about the Y number?

(By the way, what you call "X" should be called "A," and what you call "Y" shoulc be called "Z." The A number is the nucleons or mass number, the Z number is the protons or charge number.)