atomic structure

Question 1

(a) CONCEPT 1 (ATOMS)

what is the relative charge and relative mass of protons, neutrons and electrons?

Answer 1

proton: +1,1
neutron: 0,1
electron: -1,1/1840

Question 2

(a) CONCEPT 1 (ATOMS)

what is the nuclide notation for a proton, a neutron and an electron?

Answer 2

1 1p
1 0n
0 -1e

Question 4

(a) CONCEPT 1 (ATOMS)

how are electrons able to orbit around the nucleus?

Answer 4

the electrons are attracted by the protons in the nucleus via electrostatic forces.

Question 5

(b) CONCEPT 1 (ATOMS)

angle of deflection in an electric field is proportional to:

Answer 5

modulus of charge/mass

Question 6

(b) CONCEPT 1 (ATOMS)

what is the key understanding to apply for deflection in an electric field?

Answer 6

deflection only starts once the particles enter the region, and stop once the particle leaves the region (draw dotted lines to mark the region)

Question 7

(d) CONCEPT 1 (ATOMS)

how is the nuclide representation written?

Answer 7

symbol of element, nucleon number (mass number) top left, atomic number (proton number) bottom left

Question 8

(d) CONCEPT 1 (ATOMS)

what can be used to identify an element?

Answer 8

the proton number, which is unique for each element

Question 9

(e) CONCEPT 1 (ATOMS)

what is the definition of an isotope?

Answer 9

isotopes are atoms of the same element with the same number of protons but different number of neutrons.

Question 10

(f) CONCEPT 1 (ATOMS)

how are electrons arranged in an atom or ion?

Answer 10

in an atom or ion, the electrons are arranged in different shells (identified by their principal quantum number), which consists of one or more subshells. each subshell contains one or more orbitals.

Question 11

(f) CONCEPT 1 (ATOMS)

what happens when n increases?

Answer 11

when the value of n increases, the electrons are in a shell that is further away from the nucleus and of greater energy. hence the electron is less tightly bound to the nucleus.

Question 12

(f) CONCEPT 1 (ATOMS)

for principal quantun shell, n = 4, what are the sub-shells present?

Answer 12

4s, 4p, 4d, 4f

Question 13

(f) CONCEPT 1 (ATOMS)

identify the number and types of orbitals in the s, p and d sub-shells.

Answer 13

s: 1 s orbital
p: 3 orbitals, px py and pz
d: 5 orbitals, dxy, dxz, dyz, dzˆ2, dxˆ2-yˆ2

Question 14

(f) CONCEPT 1 (ATOMS)

what is an orbital?

Answer 14

an orbital represents a region of space where there is a high probability (>95%) of finding an electron. each orbital can contain a max of 2 electrons of opposite spins.

Question 15

(f) CONCEPT 1 (ATOMS)