unit 2.2 Flashcards
Where do protons and neutrons live in an atom?
The nucleus.
Where do electrons live in an atom?
The outer shells
What is the charge of a proton?
+1
What is the charge of a neutron?
0
What is the charge of an electron?
-1
What is an ion?
An atom that has either lost or gained electrons.
What is an isotope?
Different forms of the same element which have the same number of protons but a different number of neutrons/ mass.
What ate the patterns in group 1 of the periodic table?
- Density increases from top to bottom.
-melting point decreases from top to bottom.
-Boiling point decreases from top to bottom.
-Reactivity increases from top to bottom.
Why does reactivity increase down group 1?
Atoms are bigger so the outer electron is further away from the nucleus so there is less attraction meaning it’s more easily lost. (which is what they want)
How do you identify a positive ion? (halogen)
Add nitric acid and silver nitrate solution.
What is formed when testing for positive ions? (halogens)
- chloride forms a white precipitate of silver chloride.
-bromide forms a cream precipitate of silver bromide.
-Iodide forms a yellow precipitate of silver iodide.
What are the trends in group 7?
- reactivity decreases going down group 7.
-melting and boiling points increase going down group 7
Why does reactivity decrease going down group 7?
Because it gets harder to attract an extra electron because the outer shell is further away from the nucleus.
What colours are formed in the flame test? (testing for metal ions)
- Lithium = red flame
-Sodium = yellow/orange flame
-potassium = lilac flame
-calcium = brick red flame
-barium = apple green flame
