C4.1

Question 1

atoms of each element have what?

Answer 1

different proton numbers

Question 2

what does arranging the elements in order of their proton number give?

Answer 2

repeating patterns in the properties of elements

Question 3

what happened to early attempts to find connections between the chemical properties of the elements?

Answer 3

they were dismissed by the scientific community

Question 4

dobereiner 1829

Answer 4

triplets or trains of elements seemed to exist with similar properties

Question 5

new lands 1866

Answer 5

octave pattern-every 8th element to be similar

Question 6

mendeleev 1871

Answer 6

his version of periodic table
made predictions about properties and mass of yet discovered elements
left gaps to be filled when they were found

Question 7

mendeleev 2 rules

Answer 7

• order of relative atomic mass

* chemically similar in same group

Question 8

2 elements mendeleev predicted would exist and years

Answer 8

Gallium 1875

Germanium 1886

Question 9

what is a period

Answer 9

a row of elements

Question 10

alkali metals properties

Answer 10

shiny when freshly cut but tarnish rapidly in moist air due to reaction with oxygen

Question 11

where must alkali metals be stored to stop reaction with oxygen

Answer 11

in oil

Question 12

melting and boiling point as go down group

Answer 12

get lower

Question 13

alkali- hardness as go down group?

Answer 13

get softer

Question 14

Lithium reactivity

Answer 14

gentle fizzing

Question 15

Na reaction

Answer 15

faster fizzing

Question 16

potassium reaction

Answer 16

vigorous fizzing

Question 17

Lithium flame

Answer 17

bright red

Question 18

Na flame

Answer 18

bright yellow

Question 19

potassium flame

Answer 19

lilac

Question 20

alkali- reactivity as go down group?

Answer 20

more reactive

Question 21

alkali metals react with water to form what?

Answer 21

hydrogen and an alkaline solution of a hydroxide

Forumula- MOH

Question 22

alkali metals react vigorously with chlorine to form what?

Answer 22

colourless crystalline salts

formula- MCl

Question 23

Na and Cl come together to form colourless crystalline salt formula

Answer 23

Sodium Chloride

Question 24

why should you never handle alkali metals with hands

how to control?

Answer 24

corrode or explode in hand when reacts with water (sweat) - scars
•use forceps

Question 25

why do alkali metals get more reactive as go down group?

Answer 25

outer electron is further away from the influence of the nucleus and so an electron is lost more easily