Chapter 2 Atoms Ions and Compounds

Question 1

What does an atom consist of

Answer 1

A nucleus made of protons and neutrons

Question 2

What is the relative charge and relative mass of a proton

Answer 2

1+
1

Question 3

What is the relative charge and relative mass of a neutron

Answer 3

0
1

Question 4

What is the relative charge and relative mass of an electron

Answer 4

1-
1/1836

Question 5

What are elements

Answer 5

A substance made up of only one type of atom

Question 6

What identifies the element

Answer 6

The number of protons in an atom

Question 7

What is the atomic number (Z)

Answer 7

The number of protons in the nucleus of an atom

Question 8

What is an isotope

Answer 8

Atoms of the same element with different numbers of neutrons

Question 9

Do isotopes of the same element react in the same way

Answer 9

Yes

Question 10

What is the relative isotopic mass

Answer 10

The mass of an isotope compared with 1/12th of the mass of an atom of carbon-12

Question 11

What is the relative atomic mass

Answer 11

The weighted mean mass of an atom compared with 1/12th of the mass of an atom of carbon-12

Question 12

How can the percentage abundances of isotopes and their relative isotopic masses be found experimentally

Answer 12

Using a mass spectrometer

Question 13

How does a Time-of-flight mass spectrometer work

Answer 13

1. Sample is vaporised and
   then ionised to form
   positive ions:
   X(g) + e^- → X⁺(g) + e^- + e^-
2. Ions are accelerated to the same kinetic energy
3. Ions are separated according to their mass. Heavier ions move more slowly and take longer to reach the detector than lighter ions

Question 14

How do you work out A_r

Answer 14

Σ (percentage abundance x relative isotopic mass) / Σ percentage abundance

Question 15

Based on the line in the periodic table, which atoms lose electrons and which atoms gain electrons

Answer 15

• Atoms on the left lose electrons to form positive ions (cations)
• Atoms on the right gain electrons to form negative ions (anions)

Question 16

What ion does zinc form

Answer 16

Zn²⁺

Question 17

What ion does Silver form

Answer 17

Ag⁺

Question 18

what ion does Scandium form

Answer 18

Sc³⁺

Question 19

What is the formula for an ammonium

Answer 19

NH₄⁺

Question 20

What is the formula for a hydroxide ion

Answer 20

OH⁻

Question 21

What is the formula for a nitrate ion

Answer 21

NO₃⁻

Question 22

What is the formula for a carbonate ion

Answer 22

CO₃²⁺

Question 23

What is the formula for a sulphate ion

Answer 23

SO₄²⁻

Question 24

What is the formula for ammonia

Answer 24

NH₃

Question 25

What is the formula for Hydrogen sulfide

Answer 25

H₂S

Question 26

What elements are Gases

Answer 26

H₂ N₂ O₂ F₂ Cl₂ and the noble gases

Question 27

What elements are liquids

Answer 27

Br₂ Hg (mercury)