Norwich City College of Further and Higher Education

What can you remember? Atomic Structure 40 min 39 marks 1.

Atoms are made of electrons, neutrons and protons. (a)

Complete the table to show the relative mass and charge of an electron, neutron and proton. particle

relative mass

relative charge

electron neutron

–1 1

proton (4)

The diagram shows the electronic structure of an atom of an element.

× × × × × ×

× × × ×

× × ×

(b)

× × × ×

(i)

Name the element of which this is an atom. Explain your answer. ........................................................................................................................... ........................................................................................................................... (2)

(ii)

What is the atomic number of this element? ........................................................................................................................... (1) (Total 7 marks)

Norwich City College of Further and Higher Education

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2.

Boron forms an oxide which is used to make much of the glassware found in school laboratories. (a)

The element boron exists as two isotopes.

(i)

isotope

atomic number

mass number

percentage abundance

boron-10

5

10

19.7

boron-11

5

11

80.3

Compare the structures of an atom of each of the isotopes. ........................................................................................................................... ........................................................................................................................... ........................................................................................................................... (2)

(ii)

Calculate the relative atomic mass of boron. ........................................................................................................................... ........................................................................................................................... ........................................................................................................................... ........................................................................................................................... answer = ............................................ (2)

(b)

In an analysis of boron oxide, it was found that 10.0 g of boron oxide contained 3.14 g of boron. Calculate the empirical formula of boron oxide. (Relative atomic masses: B = 11.0, O = 16.0) ..................................................................................................................................... ..................................................................................................................................... ..................................................................................................................................... ..................................................................................................................................... ..................................................................................................................................... ..................................................................................................................................... empirical formula ............................................. (4) (Total 8 marks)

Norwich City College of Further and Higher Education

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3.

The table below shows some information about the isotopes of chlorine. (a)

Use information from the periodic table to help you complete the table. Isotope

Mass Number

Abundance

chlorine-35

35

75%

chlorine-37

37

25%

Number of protons in one atom

Number of electrons in one atom

Number of neutrons in one atom

...................

...................

...................

...................

...................

................... (3)

(b)

Show why the relative atomic mass of chlorine is given as 35.5. ..................................................................................................................................... ..................................................................................................................................... ..................................................................................................................................... ..................................................................................................................................... (2)

(c)

Draw a dot and cross diagram for a molecule of chlorine, showing outer electrons only.

(2)

(d)

18.39g of oxygen and 81.6lg of chlorine are combined in l00g of a compound. Calculate the empirical formula of the compound. …………………………………………………………………………………….. …………………………………………………………………………………….. …………………………………………………………………………………….. …………………………………………………………………………………….. …………………………………………………………………………………….. …………………………………………………………………………………….. (4) (Total 11 marks)

Norwich City College of Further and Higher Education

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4.

An atom of lithium has an atomic number of 3 and a mass number of 7. (a)

How many protons, neutrons and electrons are in this atom? protons ..........

neutrons ..........

electrons .......... (3)

(b)

(i)

Draw a diagram of an atom of lithium and an atom of fluorine, showing their electronic configurations, in the space below. lithium atom

fluorine atom

(3)

(ii)

Show on your diagram how these two atoms form lithium fluoride. (1)

(iii)

Name the type of bond in lithium fluoride. ........................................................................................................................... (1) (Total 8 marks)

5.

(a)

Draw a dot and cross diagram of a molecule of carbon dioxide. Show the outer electrons only.

(3)

(b)

Name and describe the type of bonding that holds the atoms together in the carbon dioxide molecule. ....................................................................................................................................... ....................................................................................................................................... (2) (Total 5 marks

Norwich City College of Further and Higher Education

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Pre-enrolment test

This is to be completed before enrolment in August