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*JUN217404101*

IB/M/Jun21/ 7404/1

E7

 AqACHEMISTRY2021

AS

CHEMISTRY

Paper 1 Inorganic and Physical Chemistry

JUNE 2021

Time allowed: 1 hour 30 minutes

Materials

For this paper you must have:

 the Periodic Table/Data Sheet, provided as an insert (enclosed)

 a ruler with millimetre measurements

 a scientific calculator, which you are expected to use where appropriate.

Instructions

 Use black ink or black ball-point pen.

 Fill in the boxes at the top of this page.

 Answer all questions.

 You must answer the questions in the spaces provided. Do not

write outside the box around each page or on blank pages.

 If you need extra space for your answer(s), use the lined pages at

the end of this book. Write the question number against your

answer(s).

 All working must be shown.

 Do all rough work in this book. Cross through any work

you do not want to be marked.

Information

 The marks for questions are shown in brackets.

 The maximum mark for this paper is 80.

Advice

You are advised to spend about 65 minutes on Section A and 25 minutes on Section B.

For Examiner’s Use

Question Mark

1

2

3

4

5

6

7

8

9

10

Section

B

TOTAL

2

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outside the

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Section A

Answer all questions in this

section.

box

0 1 This question is about atomic structure.

0 1 . 1 Figure 1 is a model proposed by Rutherford to show the structure of an

atom.

Figure 1

State two features of the current model that are not shown in the Rutherford

model.

[2 marks]

Feature 1 of the current model

Feature 2 of the current model

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0 . 1 2A sample of tin is analysed in a time of flight mass spectrometer.

The sample is ionised by electron impact to form 1+ ions.

Table 1 shows data about the four peaks in this spectrum.

Table 1

m/z Percentage abundance

11

2

22.41

11

4

11.78

11

7

34.97

12

0

To be determined

Give the symbol, including mass number, of the ion that reaches the

detector first.

box

Calculate the relative atomic mass of tin in this

sample. Give your answer to 1 decimal place.

[4 marks]

Symbol of ion

Relative atomic mass

Do not write 6

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