F4 C4 CHEM (GROUP 1 4.4)

Question 1

whats group 1 known as?

Answer 1

alkali metal

Question 2

are group 1’s elements metal? why?

Answer 2

yes because group 1 -13 are metals

Question 3

first 3 elements in gorup 1?

Answer 3

lithium (Li)
sodium (Na)
pottasium (K)

Question 4

which characteristic of these elements determines them to be in group 1?

number of valence electrons?

Answer 4

they have 1 valence electron

Question 5

alkali metals appear as?

Answer 5

shiny grey solids

Question 6

compare the hardness of alkali metal to a normal metal

Answer 6

alkali metals are soft that they can be cut by knife

Question 7

compare the density of alkali metal to a normal metal

Answer 7

an alkali metal has a low density (float) compared to a normal metals which has a high density (sink) in water

Question 8

compare the melting and boiling point of alkali metal to a normal metal

Answer 8

an alkali metal has a low melting and boiling point compared to a normal metal

Question 9

why is the melting and boiling point of an alkali metal low?

Answer 9

shells filled with electrons of group 1 elements are attracted by weak metallic bond. little heat is required to overcome the forces of attraction

Question 10

can group 1 elements conduct heat and electricity?

Answer 10

yes, these metals are good conductors

Question 11

explain the density going down the group

Answer 11

moving down the group, the density increases because the increase in mass is greater than the increase in volume

Question 12

explain the atomic size going down the group

Answer 12

going down the group, the atomic size increases because number of shells filled with electrons increases

Question 13

explain the melting and boiling point going down the group

Answer 13

going down the group, the melting and boiling point decreases. this is because going down the group the atomic size increases and the the metallic bond is becoming weaker. little heat is required to overcome the forces of attraction

Question 14

explain the hardness going down the group

Answer 14

alkali metals becomes softer going down the group

Question 15

group 1 elements are very reactive. why?

Answer 15

group 1 elements are not stable yet. they’ll donate/lose/share one valence electrons to achiveve stable duplet/octet electron arrangement

Question 16

what happens after the grp 1 element loses its electron?

Answer 16

these alkali metals becomes a positive ion with a +1 charge.
exp : Na+, K+

Question 17

changes in chemical properties of alkali metals is from which aspect?

Answer 17

reactivity

Question 18

what happens to the reactivity of the group 1 elements going down the group?

Answer 18

going down the group, the reactivity increases. this is because it’ll be easier for elements to lose/donate one electrons.

Question 19

what’s another word for *increasing reactivity *?

Answer 19

more electropositive

Question 20

Group 1elements can react with?

theres 3 things

Answer 20

water, oxygen, chlorine

Question 21

whats the chemical equation for reaction on group 1 elements with water

Answer 21

Alkali metal + water—>
alkali + hydrogen

example (unbalanced equation) : Na + H20 –> NAOH (sodium hydroxide) +H2

Question 22

explain the reaction of lithium (Li), an alkali metal, with water

Answer 22

• moves slowly on the surface of water with a “hiss” sounds
• produces colourless solution
• the colourless solution turns red litmus paper into blue

Question 23

explain the reaction of sodium (Na), an alkali metal, with water

Answer 23

• moves rapidly on the surface of water with a “hiss” sound
• burn with yellow flame
• produces colourless solution
• the colourless solution turns red litmus paper into blue (alkaline solution)

Question 24

explain the reaction of pottasium (K), an alkali metal, with water

Answer 24

• moves very rapidly on the surface of water with a “hiss” sound
• burn with purple flame
• produces colourless solution
• the colourless solution turns red litmus paper into blue (alkaline solution)

Question 25

what's the chemical equation of the reaction between alkali metal and oxygen | general equation

Answer 25

alkali metal + oxygen ---> metal oxide (white solid) | example (unbalanced equation) : Na + O2 --> Na2O

Question 26

can metal oxide (alkali metals that reacted with oxygen) dissolve in water?

Answer 26

yes metal oxide produces alkali when dissolved in water again Na2O + H2O --> 2NAOH (balanced equation)

Question 27

does the alkali metal produce hydrogen when dissolve in water? what about metal oxide?

Answer 27

yes alkali metal does but however metal oxide does not produce hydrogen alkali metal : produce alkali + hydrogen metal oxide : produce alkali only

Question 28

**EXPERIMENT** explain the reaction of lithium (Li) with oxygen

Answer 28

- lithium burns slowly with red flame - white solid is produced - white solid dissolves in water to produce colourless solution - colourless solution changes red litmus paper to blue

Question 29

**EXPERIMENT** explain the reaction of sodium (Na) with oxygen

Answer 29

- sodium burns brightly with yellow flame - white solid is produced - white solid dissolves in water to produce colourless solution - colourless solution changes red litmus paper to blue

Question 30

**EXPERIMENT** explain the reaction of pottasium (K) with oxygen

Answer 30

- pottasium burns very brightly with purple flame - white solid is produced - white solid dissolves in water to produce colourless solution - colourless solution changes red litmus paper to blue

Question 31

other than oxygen and water, gorup 1 elements can also react with ?

Answer 31

Chlorine

Question 32

whats the chemical equation for the reaction of group 1 with chlorine

Answer 32

alkali metal + chlorine ---> metal chloride (white solid) example (balanced equation) : 2Na + Cl2 --> 2NaCl

Question 33

alkali metals are shiny ____ .

Answer 33

grey solid

Question 34

alkali metals when reacted with oxygen and chlorine will produce ____ solid

Answer 34

white

Question 35

Can group 1 chloride dissolve in water? if yes, what's produced?

Answer 35

Yes group 1 chloride dissolves in water to produce **neutral** solution | Note : group 1 oxide and hydroxide produces alkaline solution

Question 36

**EXPERIMENT** explain the reaction of lithium (Li) with chlorine

Answer 36

- lithium burns slowly with red flame - white solid is produced

Question 37

**EXPERIMENT** explain the reaction of sodium (Na) with chlorine

Answer 37

- sodium burns brightly with yellow flame - white solid is produced

Question 38

**EXPERIMENT** explain the reaction of pottasium (K) with chlorine

Answer 38

- pottasium burns very brightly with purple flame - white solid is produced

Question 39

List 2 safety precautions while handling alkali metals

Answer 39

1. store alkali metals in parrafin oil 2. put on gloves and take alkali metals using a forcep 3. (extra) use small amounts of alkali metals as they're very reactive