Fundamental Chemistry

Question 1

Define compound

Answer 1

Two or more elements chemically bonded

Question 2

Define element

Answer 2

Substance made up of only one type of atom

Question 3

Mass of a proton

Answer 3

1 AMU

Question 4

Mass of a neutron

Answer 4

1 AMU

Question 5

Mass of an electron

Answer 5

Almost 0, 1/2000 AMU

Question 6

Define mass number

Answer 6

Number of protons + neutrons

Question 7

Define atomic number

Answer 7

Number of protons (in the nucleus)

Question 8

Explain how a chlorine atom becomes a chlorine ion

Answer 8

Gains one electron

Question 9

Explain how a sodium atom becomes a sodium ion

Answer 9

Loses one electron

Question 10

Explain how an oxygen atom becomes an oxide ion

Answer 10

Gains two electrons

Question 11

Explain how a magnesium atom becomes a magnesium ion

Answer 11

Loses two electrons

Question 12

Charge of a proton

Answer 12

+1

Question 13

Charge of a neutron

Answer 13

0

Question 14

Charge of an electron

Answer 14

-1

Question 15

Define a molecule

Answer 15

Two or more atoms bonded together

Question 16

Formula of sodium hydroxide

Answer 16

NaOH

Question 17

Formula of magnesium chloride

Answer 17

MgCl₂

Question 18

John Newlands and Mendeleev arranged their periodic table in order of…

Answer 18

atomic mass

Question 19

The modern periodic table is arranged in order of…

Answer 19

atomic number (proton number)

Question 20

Explain why Mendeleev left gaps in his periodic table

Answer 20

to make the pattern fit for undiscovered elements

Question 21

Explain why potassium and sodium are in the same group of the periodic table

Answer 21

They both have one electron in their outer shell They react similarly

Question 22

Describe how alkali metals react with water

Answer 22

-Bubble/Fizz/Effervesce -Turn indicator purple -Move about on the surface of the water -Sodium melts in a ball -Potassium burns with a lilac flame

Question 23

Write a symbol equation for the reaction of sodium with water

Answer 23

2Na + 2H₂O –> 2NaOH + H₂

Question 24

Name the typical properties of transition metals

Answer 24

-Good conductors of heat and electricity -Hard and strong -High density -High melting point -Form coloured compounds -Form ions with different charges (i.e. Fe²⁺ and Fe³⁺

Question 25

Name one similarity and difference between the properties of copper and lithium

Answer 25

Similarities - conduct electricity Differences - lithium is more reactive, lithium is less dense, lithium is softer, lithium has a lower melting point

Question 26

Describe the trend in reactivity of the group 1 metals as you go down the group

Answer 26

Reactivity increases

Question 27

Describe the trend in melting point as you go down group 7

Answer 27

Melting point increases (fluorine is a gas, iodine is a solid)

Question 28

Describe the trend in reactivity as you go down group 7

Answer 28

Reactivity decreases

Question 29

Explain why chlorine and bromine are group 7 of the periodic table

Answer 29

Both have 7 electrons in their _outer_ shell

Question 30

Finish the following word equation Bromine + potassium iodide --\>

Answer 30

Potassium bromide + iodine

Question 31

Explain why chlorine can displace bromine from potassium bromide

Answer 31

chlorine is more reactive

Question 32

Name the ion that turns universal indicator purple

Answer 32

OH^-

Question 33

Explain why potassium is more reactive than sodium

Answer 33

-Potassium has a greater atomic radius/more energy levels/more shells -there is less attraction between the outer electron and the nucleus/more shielding -Potassium loses an electron easier

Question 34

Explain why fluorine is more reactive than chlorine

Answer 34

-Fluorine has a smaller atomic radius/less energy levels/less shells -there is greater attraction between the outer shell and the nucleus/less shielding -fluorine **gains** an electron **easier**

Question 35

Name one use for the transition metals

Answer 35

Catalysts

Question 36

Name pieces of apparatus A, B, C What is the name of this separation process?

Answer 36

A = thermometer B = condenser C = (round bottomed) flask Fractional Distillation

Question 37

A student is given a mixture of salt and sand. Describe a method the student could do to separate the mixture naming the apparatus they should use.

Answer 37

- Pour the mixture into a beaker - Add water to the beaker - Stir until the salt dissolves - Filter the mixture - Remove the residue (sand) - Dry the sand in an oven - Place the filtrate (salt solution) in an evaporating basin - Heat the solution with a Bunsen burner until the water evaporates - Cool and dry the salt with an oven

Question 38

Explain why chlorine's relative atomic mass is 35.5

Answer 38

Relative atomic mass is an average mass Chlorine exists as Cl- 35 and Cl-37 75% is Cl-35 and 25% is Cl-37 (35 x 75 ÷ 100) + (37 x 25 ÷ 100) = 35.5

Question 39

Explain why Mendeleev swapped Tellurium and Iodine's position in his periodic table.

Answer 39

- Iodine has similar properties to other group 7 elements - Iodine had similar chemical reactions to other group 7 elements - Iodine is also diatomic

Question 40

What subatomic particle did James Chadwick discover?

Answer 40

Neutron

Question 41

How did Mendeleev's periodic table become accepted by scientists?

Answer 41

They discovered the elements he'd left gaps for and they had similar properties to those he'd precited