(a)  (5 marks) For each of parts (a) – (j), write the answer on the line provided. Each part is worth ½ mark.

(i)   Write the formula for the compound composed of K+ and O2- ions.

(ii)  C20H6 I4Na2O5 is used as a red colouring in foods. Give the number of atoms in this formula.

(iii) Write the symbol of the ion that has 16 protons and 18 electrons.

(iv) What is the maximum number of electrons that can exist.in a pz orbital?

(v)  Which element is assigned the highest electronegativity?

(vi) Classify antimony (Sb) as a metal, nonmetal, or metalloid.

(vii)  State the charge of an iron ion with 23 electrons.

(viii) Write the number of group of the periodic table   to which the element with the symbol Se belongs.

(ix)   Name the process in which a gas is converted to a liquid.

(x)    What term is used to describe different physical forms of the same element?

K2O

(b)    (3 marks) Classify each of the following mixtures as heterogeneous or homogeneous by

circling the appropriate word. Each part is worth 1½ marks.

(i)   a cup of chocolate milk heterogeneous / homogeneous (circle one) Justify your choice

Chocolate milk has same uniform appearance and composition throughout

(ii)  Salt and pepper in a bowl heterogeneous / homogeneous (circle one)

Justify your choice

It is a mixture having a non-uniform composition

(c)     (1 mark) A sample of oil has a mass of 65.0 g and a volume of 80.0 mL. What is the density of the oil?

D = mass/volume = 65.0 g/80.0 mL = 0.81 g mL-1

(d)  (2 marks) Identify each of the following properties as being either physical or chemical by

circling the appropriate word. Each part is worth ½ mark.

(i)   The density of water at 4°C is 1.00 g mL- 1

(ii)  Chlorine gas has a green-yellow colour

(iii) Gold does not form a gold oxide coating

(iv) Chlorine bleach is used to remove stains

physical /  chemical

physical /  chemical

physical /  chemical

physical /  chemical

(e)  (1 mark) Define the term “ion” .

An ion is an electrically charged atom or bonded group of atoms

(f)   (2 marks) Choose the term which best fits descriptions given in parts (i) – (iv), and write that

term on the line to the right of the part. Each part is worth ½ mark.

Melting Freezing Sublimation Condensation

(i)   Butter in a hot pan turns to a liquid

(ii)  Foggy appearance of car windows in cold weather

(iii) A piece of dry ice (solid carbon dioxide) changes to a gas

(iv) Ice forms on the surface of a lake in winter

___M__e_lti__n________

___Condensation_____

_________________

____F_r_e_en_______

QUESTION 2: (16 marks TOTAL)

(a)   (2 marks) Balance the following chemical equations by placing coefficients on the lines

provided. Each part is worth 1 mark.

(i)     __1___ Al2 S3(s)  + __6___ H2O(l) 2_____ Al(OH)3(s)  + __3___ H2 S(g) (ii) 2_____ Fe(OH)3(s) __1___ Fe2O3(s)  + __3___ H2O(l)

(b)    (3 marks) Write the electron configuration using s, p, d notation for the following. Each

part is worth 1 mark.

(i)       Bromine 1s2__2s2___2p6____3_s2__3_p_6_4_s2__3_d_10__4_p_5__or__ [Ar] 4s2 3d_10_ 4p5 (ii)      Bromide ion 1s2__2_s2__2_p_6_3_s_2_3_p_6_4s__2_3d1___0_4p6____or____[A__r_]_4_s2__3_d_10__4p6 (iii)    Explain why the radius of a bromide ion is bigger than the radius of a bromine atom

Br- has 36 electrons whereas its nucleus contains 35 protons only. Br- radius is larger because of electron-electron repulsion and weaker pull by nucleus

(c)  (1 mark) Consider the following velocity distribution curves A and B. If the plots represent the velocity distribution of 1.0 L of H2(g) at 25°C verses 1.0 L of Cl2(g) at 25°C, which plot corresponds to each gas? Explain your reasoning.

A: Cl2(g) & B: H2(g)

At a given temperature, lighter molecules (H2) move faster than heavier molecules (Cl2). At a given temp, a gas with lower molar mass has higher most probable speed.

(d)  (1 mark) Draw the Lewis structure of Carbon Tetrachloride (CCl4) in the space below.

(e)  (1 mark) Using VSEPR theory, predict the shape that describes the arrangement of atoms

about the carbon atom in methane, CH4.

H

C

H

(f)   (1 mark) Define the term “evaporation” .

Conversion of liquid to gas at temperatures below the boiling point

(g)  Write the name for each of the following compounds on the line to the right:

(i) (½ mark) Na2 SO4

(ii) (½ mark) NCl3

____S_o_d_iu__m__u_l_p_h_a_t_e_____

___N__it_r_o_e_n_t_r_ichlo____r_ide_____

(h)  Write the formula of the following compounds on the line to the right.

(i) (½ mark) Cobalt(II) sulphide             _________________

(ii) (½ mark) Sulfur dichloride SCl2

(i)    (2 marks) Write the symbols 6+ (partial positive) and 6- (partial negative) over the appropriate atoms in polar bonds. Each part is worth ½ mark.

(i)   C Cl                   (ii)   N H               (iii)  P Cl              (iv)  O H

(j)    (2 marks) For parts ( 1) to (4), circle the correct answer. Each part is worth ½ mark.

1.  NaCl is a face-centred cubic lattice of Cl- ions with each Cl- ion is surrounded by ______ Na+ ions.

(i)  2                       (ii)  4                          (iii)  6                        (iv)  8

2.   Crystals which are good conductor of electricity and heat are known as _______ crystals.

(i)  ionic                (ii)  covalent               (iii)  molecular           (iv)  metallic

3.   Which of the following is an example of hydrogen bonded molecular crystal?

(i) HCl                   (ii) H2                                     (iii) Ice                       (iv) CH4

4.   If the temperature of a fixed amount of gas decreases and the pressure remains unchanged,

(i)   its volume increases                            (ii)  its volume decreases

(iii)  its volume is unchanged                     (iv)  its density decreases

(k) ( 1 mark) Arrange the following set of elements in order of increasing atomic size: B, C, K, and Na

__C____ < B______  < __Na____ < K______

QUESTION 3: (20 marks TOTAL)

(a) (8 marks) Each of parts (i) – (x) is worth ½ mark, (xi)-(xiii) are worth 1 mark each. The compounds in the grid below may be used in more than one answer.

For parts (i) – (x) give in the box to the right the letter of one compound (there may be more than one right answer) which:

(xi)     (1 mark) Compound C can exist as

enantiomers.  Complete the  structure  of the

enantiomer of Compound C.

The framework for the enantiomer has been

provided in the box to the right.

(xii)  (1 mark) The two enantiomers of C are

an example of:

constitutional / conformational / configurational isomers.      (circle one)

(xiii) (1 mark) Which compound from&n