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Flashcards in C4.1 Deck (51):
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1. What do atoms of each element have?

-atoms of each element have different proton numbers, as it is the proton number which determines what element it is

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2. What happens when you arrange the elements in order of their proton numbers?

-it gives repeating patterns in the properties of elements

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3. What happened to early attempts to find connections between the chemical properties of the elements and their relative atomic mass?

-they were dismissed by the scientific community

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4. Who were significant individuals in the history of the development of the Periodic Table?

-Döbereiner
-Newlands
-Mendeleev

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4. What were the elements originally arranged by? Why?

-relative atomic mass as that was the only thing they could measure

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4. What contribution did Döbereiner have to the development of the Periodic Table?

-1828
-triads:
similar chemical properties
middle element of triad had average ram of the other two

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4. What contribution did Newlands have to the development of the Periodic Table?

-1865
-arranged in order of ram
-octaves (each 8th element had similar properties)
-third row broke down as he didn’t leave gaps

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4. Why was Newlands work criticised?

-groups contained elements that didn’t have similar properties
-he mixed up metals and non-metals
-he didn’t leave gaps for undiscovered elements

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4. What contribution did Mendeleev have to the development of the Periodic Table?

-1869
-arranged in order of ram
-left gaps so elements had similar properties in vertical rows
-gaps left for undiscovered elements

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5. How did Mendeleev use his Periodic Table to predict the existence of unknown elements?

-he left gaps for undiscovered elements
-newly discovered elements fit into gaps= supports his arrangement

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7. What do all the elements in each group have?

The elements in a group have similar properties

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7. What is a group of elements?

A group of elements is a vertical column in the Periodic Table

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8. What is a period?

A period is a row of elements in the Periodic Table

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9. What elements on the periodic table are metal and non-metal?

Metals are on the left side of a diagonal line from the bottom of boron to the bottom of astatine, non-metals are on the right

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11. What are Group 1 metals also known as?

The alkali metals

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11. Which elements are in group 1? What are their chemical symbols?

-lithium= Li
-sodium= Na
-Potassium= L

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12. What is a visible property of group one metals?

The alkali metals are shiny when freshly cut but tarnish rapidly in moist air due to reaction with oxygen

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13. What are patterns in Group 1 metals?

DOWN THE GROUP
-more reactive
-higher density
-lower melting point
-lower boiling point

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13. Why does REACTIVITY INCREASE down group 1 metals?

-Wants to lose 1 electron to be a full shell
Increased atom size= outer electron further away from nucleus= more easily lost

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13. Why does DENSITY INCREASE down group 1 metals?

-Because the atoms are bigger so have more mass

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13. Why does MELTING/BOILING POINT DECREASE down group 1 metals?

- Increased atom size= increase in distance of ions to delocalised electrons= weaker metallic bond (electromagnetic force is more spread out)

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14. What is the reaction between lithium and water like?

-floats on water
-gently fizzes and gives of hydrogen
-dissolves= lithium hydroxide

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14. What is the reaction between sodium and water like?

-floats on water
-heat= melts= silvery ball
-hydrogen given off
-dissolves= sodium hydroxide

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14. What is the reaction between potassium and water like?

-floats on water faster
-heat= melts= silvery ball
-hydrogen given off, and ignited to as enough energy= lilac flame
-dissolves= lithium hydroxide

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15. What is formed when alkali metals react with water?

-an alkaline solution of a hydroxide of the metal with the formula (M)OH [‘metal’ hydroxide]

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15. What are examples of this hydroxide solution?

-lithium hydroxide (LiOH)
-sodium hydroxide (NaOH)
-potassium hydroxide (KOH)

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16. What happens in the reaction between alkali metals and chlorine?

alkali metals react vigorously with chlorine to form colourless, crystalline salts with the formula (M)Cl [‘metal’ chloride]

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16. What are examples of colourless crystalline salts produced in the reaction between alkali metals and chlorine?

-lithium chloride (LiCl)
-sodium chloride (NaCl)
-potassium chloride (KCl)

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17. What happens to the reactivity and properties of alkali metals as the group is descended?

-more reactive
Wants to lose 1 electron to be a full shell
Increased atom size= outer electron further away from nucleus= more easily lost

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17. What are examples to show that the alkali metals become more reactive as the group is descended?

-more violent the reaction between an alkali metal and cold water, the more reactive it is

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18. What are the hazard symbols?

-explosive, toxic, corrosive, oxidizing, and highly flammable

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18. What does EXPLOSIVE mean? What is an example?

-can explode
-e.g. some peroxides

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18. What does TOXIC mean? What is an example?

-can cause death if swallowed, breathed in, or absorbed through skin
-e.g. Hydrogen cyanide

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18. What does CORROSIVE mean? What is an example?

-attacks and destroys living tissues, like eyes and skin
-e.g. concentrated sulphuric acid

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18. What does OXIDISING mean? What is an example?

-provides oxygen so other materials can burn more
-e.g. liquid oxygen

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18. What does HIGHLY FLAMMABLE mean? What is an example?

-catches fire easily
-e.g. petrol

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19. What are the necessary precautions when working with Group 1 metals and alkalis?

-stored in oil as react vigorously with water
-fire extinguisher close as reactive and spontaneously combust
-don’t touch it as can react with sweat= heat and corrosive hydroxide
-apparatus needs to be dry as reacts with water
-can’t touch skin or eyes as alkaline solutions are corrosive

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20. What are Group 7 metals also known as?

The halogens

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20. Which elements are in group 7? What are their chemical symbols?

Chlorine- Cl2
Bromine- Br2
Iodine- I2

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21. What are the states of halogens at room temperature and pressure?

Fluorine - gas
Chlorine - Dense gas
Bromine - Volatile liquid
Iodine - Crystalline solid

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22. What are the colours of these halogens in their normal physical state at room temperature and as gases?

Fluorine - Yellow
Chlorine - green
Bromine - Orange
Iodine - Dark grey (gas= Purple vapour)

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23. What are the molecules of halogens?

The halogens consist of diatomic molecules

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24. What are patterns in Group 7 elements?

What happens as you go DOWN the group:
-Become less reactive
Wants to gain 1 electron to be a full shell
Increased atom size= outer electron further away from nucleus= harder to gain
-Have a higher melting/ boiling point
Van der Waals dispersion forces

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25. What happens to the reactivity of halogens as you go down the group?

-reactivity decreases

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25. What are examples that show that reactivity of halogens decreases as you go down the group?

-reactions with alkali metals become less vigorous down the group
-reactions with iron become less vigorous down the group
-displacement reactions shows which elements (ones further up) are more reactive than others

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26. What happens in the reaction between a halogen and an alkali metal (to show decreasing reactivity down the group)?

-halogen + alkali metal (e.g. lithium, sodium, potassium)= salts called metal halides (e.g. sodium chloride, potassium bromide, lithium iodide)

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26. What happens in the reaction between a halogen and iron (to show decreasing reactivity down the group)?

-halogen + iron= coloured solids called iron halides

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26. What happens in displacement reactions with halogen (to show decreasing reactivity down the group)?

-more reactive element from compound displaces less reactive element (pushes it out)

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27. What are the necessary precautions when working with the halogens?

-don’t get in body as chlorine+ iodine= toxic
-careful with fluorine as is most reactive
-avoid contact with skin as liquid bromine is corrosive
-in fume cupboard as they have poisonous vapours which irritate eyes and lungs

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30. What must charges add up to in compounds?

0

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28. What are examples of halides?

-chlorides
-bromides
-iodides