Magnesium ribbon reacts with dilute hydrochloric acid at room temperature.

(a) State three ways by which the reaction can be made to proceed faster

(b) Write an equation for the reaction.

How many atoms are contained in 0.2moles of nitrogen? [NA=6.02×10²³]

• A. 1.20×10²³
• B. 2.41×10²³
• C. 3.62×10²³
• D. 4.82×10²³

Which of these is not a physical property of metals?

• A) electrical conductivity
• B) lustre
• C) ductile
• D) resistant

The functional group(s) of an amino acid is/are

• A)
  NH\(_2\), -COOH
• B)
  C\(_n\)H\(_{2n+1}\), -COOH
• C)
• D)
  COOH, CONH\(_2\)

The gas given off when NH₄Cl is heated with an alkali is

• A. H₂
• B. Cl₂
• C. N₂
• D. NH₃

Which of the following alloys does not contain copper? l. Brass II. Bronze III. Steel

• A. l only
• B. ll only
• C. lll only
• D. ll and lll only

a) Define the following in term:. of electron transfer: (i) oxidation; (ii) reduction.

(b)(i) Determina the oxidation stale of phosphorus in each of the following structures: I. POCI\(_3\) II. PH\(_3\).

(ii) State with reasons whether the following compounds will form acidic, neutral or basic aqueous solutions: I. NaNO\(_3\) II. Na\(_2\)H\(_4\)CI; Ill. Na\(_2\)CO\(_3\).

(c) Consider the set-up

(i) What is the gas produced in the experiment illustrated by the set-up above?

(ii) Name the method of collection of gas

(iii) Give a reason for your answer in (c)(ii) above

(iv) State the function of the concentrated H\(_2\)SO\(_4\) in the conical flask

(v) Give of collection of the gas one I. physical property; II. chemical property of the gas

(vi) State one chemical test to identify the gas.

(d) A 4.3 g hydrated sodium tetraoxosulphate (VI) (Na\(_2\)SO\(_4\).xH\(_2\)O) was heated to remove the water of crystallization. The remaining anhydrous salt had a mass of 2.12 g. Calculate the value of x in the t I hydrated salt. [H = 1; O = 16; Na = 23; S = 32 ]

Detergents are better than soaps for laundry because

• A.detergents are syntheticabile soaps are not
• B. Detergent are more soluble in water than soap
• C. Scum is precipitated when soap are used with hard water but not with detergent
• D. Soaps are in bar while detergent are I powder form

The shape of CH₄ is

• A. linear
• B. planar
• C. pyramidal
• D. tetrahedral

An increase in temperature causes an increase in pressure of a gas in a fixed volume due to an increase in the?

• A. number of molecules of the gas
• B. density of the gas molecules
• C. number of collisions between the gas molecules
• D. number of collisions between the gas molecules and the walls of the container