Which of the following lowers the activation energy of a chemical reaction?

Which of the following statements about ideal gases is/are correct?

I. The cohesive forces between their particles are negligible

ll. The have no definite volume but occupy the volume of their containers

III. They are not compressible

IV. Their particles collide with loss of energy

Which of the following contains co-ordinate covalent bond?

What is the value of x in the following equation? Cr₂O₇^2- + 14H⁺ + xe- → 2Cr³⁺ + 7H₂O

What type of reaction is involved when wood shavings produce a brown gas with concentrated HNO₃?

Helium is preferred to hydrogen in filling balloons because hydrogen

It can be concluded that gastric juice

Which of the following occurs when a solution of CuSO₄ is electrolysed using copper electrodes?

The property of calcium chloride which makes it useful as a drying agent is that it is

Which of the following compounds dissolves in water to form a solution with pH below 7?

30cm³ pf hydrogen at s.t.p combine with 20cm³ of oxygen to form steam according to the following equation 2H_2(g) + O_2(g) → 2H₂O_(g). Calculate the total volume of the gaseous mixture at the end of the reaction

Two radioactive elements Q and S have half-life periods of 10 hours and 20 hours respectively. Therefore

What is the effect of using vanadium (V) oxide as catalyst in the reaction represented by the following equation? 2SO₂ + O₂ ⇌ 2SO₃; ∆H = - xKJmol-¹

Exhaust fumes discharged from a smoky vehicle gradually become invisible as a result of

Which of the following substances decomposes when an electric current is passed through it?

Gas molecules are said to be perfectly elastic because

Which of the following would dissolve in warm dilute H₂SO₄ without effervescence, to give a blue solution?

What is the oxidation number of nitrogen in AI(NO₃)₃?

What volume of hydrogen is produced at s.t.p. When 2.60 g of zinc reacts with excess HCI according to the following equation? Zn_(s) + 2HCI_(aq) → ZnCI _2(aq) + H_2(g) [Zn = 65; 1 mole of a gas occupies 22.4dm³ at s.t.p]

A radioactive solid is best stored

Chemical equilibrium is attained when

Electrovalent compounds are characterized by

Which of the following methods is suitable for the preparation of an insoluble salt?

Which of the orbitals 4s, 4p, 4d and 4f has the lowest energy?

The presence of unpaired electrons in an atom of a transition metal gives rise to

If the solubility of KHCO₃ is 0.40 mole dm^-3

Consider the reaction represented by the following equation: H_2(g) + 1_2(g) → 2HI_(g). The number of effective collisions of molecules of the reactants decreases as

A reaction is represented by the equation below. A_2(g) + B_2(g) 2AB_(g); ∆H = +X kJmol^-1 Which of the following statements about the system is correct?

What will be the effect of increase in pressure on the following system at equilibrium? 2NH_2(g) N_2(g) + 3H_2(g)

Which of the following movements can be described as random motion?

Given that the order of reactivity of four metals is P>Q>R>S, which of the following reactions is feasible?

The atoms of four elements are represented as ₂₀Q, ₁₆R, ₁₀S and ₈T Which of the elements would be unreactive?

Rusting of iron is an example of

What mass of copper would be deposited by a current of 1. 0 ampere passing for 965 seconds through copper (ll) tetraoxosulphate (IV) solution? [Cu = 63.5; 1F = 96500C]

Which of the following will produce oxygen and hydrogen during its electrolysis using platinum electrode?

One mole of a compound M(HCO₃)₂ has a mass of 162g. Calculate the relative atomic mass of M. [H = 1, C =12, O = 16]

The liquid product of the destructive distillation of coal is

What does ∆H represent in the following equation ? Cl_(g) + e- → CI- _(g); ∆H = - 363 kJ mol-¹

Consider the following equation: Ag⁺ _(aq) + CI-_(aq) → Ag⁺CI- _(s) ; ∆H = _65.7 kJmol^-1. From the equation, it can be deduced that

Which of the following compounds dissolves in water to give an alkaline solution?

Petrol consists mainly of

The crystal layers in graphite are held together by

Which of the following pairs of reagents recat to produce hydrogen?

Substances which absorb water from the atmosphere without dissolving in it are said to be

Which of the following non-metals reacts most readily with metals?

If an element with high electron affinity combines with another element with low ionization energy the bond formed will be mainly

Chlorine atom forms CI by

P _Total = F₁ + P₂ + P ₃ + .........P_n' where P _Total is the pressure of a mixture of gasses. The equation above is an expression of

In the Periodic Table, the elements that loss electrons most readily belong to

Elements which belong to the same group in the Periodic Table are characterized by

Elactrostatic force of attraction between sodium ion and halide ion is greatest in

What is oxidized in the reaction represented by the following equation? 3CU + 8HNO₃ → 3Cu(NO₃)₂ + 2NO + 4H₂O

An exothermic reaction is one which involves

How many electrons are removed from Cr^2- when it is oxidized to CrO₄^2-?

The type of chemical bond that exists between potassium and oxygen in potassium oxide is

Which of the following properties increases down a group in the Periodic Table?

Which of the following procedures is suitable for identifying the food colouring added to a pastry sample?

Which of the following increases as boiling water changes to steam?

Which of the following features of a human skeleton can be determined by carbon-dating?

Which of the following is not correct about oxidation number convention? The oxidation number of a/an

A sheet of paper is placed in the path of a beam from a radioactive source. The emissions that pass through the paper consist of

The gas evolved when dilute tetraoxosulphate (VI) acid reacts with sodium hydrogen trioxocarbonate (IV) is

The spontaneity of a chemical reaction is determined by the change in the

0.10 mol dm^-3 NaCI conducts electricity better than 0.10 mol dm^-3 CH₃COOH because the solution of NaCI

Metals are said to be malleable because they

When alkanols react with sodium, the ga evolved is

Equal volumes of CO₂ cnd CO at s.t.p have the same

Which of the following will displace copper from a solution of copper (ll) salt?

Aluminium is extracted from

Pipe-borne water is usually chlorinated in order to

A concentrated solution containing H⁺, Cu²⁺,OH^- and CI^- was electrolysed using platiunm electrodes which of the ions will be discharged at the cathods?

What is responsible for metallic bonding?

What is the shape of a molecule of CCI₄?

What is the function of sulphur (IV) oxide in the reaction represented by the following equation? SO _2(aq) + 2H₂S_(g) → 3S _(s) + 2H ₂O _(l)

Which of the following can undergo both addition reactions and substitution reactions?

Dehydration of ethanol produces

A finely divided from of a metal burns more readily in air than the rod from because the rod has

A mixture of calcium chloride and calcium trioxocarbonate (IV) in water can be separated by

Pauli Exclusion Principle is related to

Calcium atom ionizes by