elements and atomic structure

Question 1

what are elements?

Answer 1

substances that contain only one type of atom

Question 2

what do atoms of one electron have?

Answer 2

the same number of protons and electrons

Question 3

where are electrons shown?

Answer 3

in the periodic table

Question 4

what are atoms composed of?

Answer 4

electrons surround a nucleus consisting of protons and neutrons

Question 5

what is the relative mass, relative charge and location of protons?

Answer 5

1, +1, in the nucleus

Question 6

what is the relative mass, relative charge and location of neutrons?

Answer 6

1, 0, in the nucleus

Question 7

what is the relative mass, relative charge and location of electrons?

Answer 7

1/2000, -1, around the nucleus

Question 8

what is the atomic number?

Answer 8

the number of protons in an atom

Question 9

how is the periodic table arranged?

Answer 9

in increasing order of atomic number

Question 10

the mass number of an atom =

Answer 10

number of protons + number of neutrons

Question 11

why are electrons important?

Answer 11

they are the bit of the electron that takes part in bonding

Question 12

how many electrons does shell 1 hold?

Answer 12

2

Question 13

how many electrons does shell 2+ hold?

Answer 13

8

Question 14

how would chlorine (17 electrons) be written?

Answer 14

2, 8, 7

Question 15

how do you know what group an atom is in from its electronic configuration?

Answer 15

from the number of atoms on the outermost shell e.g chlorine is in group 7

Question 16

how do you know what period (row) an atom is in from its electronic configuration?

Answer 16

from the number of shells with electrons in them e.g chlorine is in period 3

Question 17

what makes an atom stable

and what does this cause?

Answer 17

if its shells are all full

and that the noble gases in group 0 / 8 are nonreactive

Question 18

what do elements do to have full outer shells?

Answer 18

they exist as diatomic molecules e.g. hydrogen (H2), oxygen, chlorine, bromine, iodine, nitrogen