The existance of two or more forms of the same element in the same physical state is known as

A. allotropy

B. resonance

C. hybridization

D. isotopy

E. isomerism

When an atom gains an electron, it becomes properties

A. chemically inactive

B. negatively charged

C. oxidized

D. a cation

E. a complex ion

The alkali metals exhibit similar chemical properties because

A. they occur in the combined state

B. they have the same number of vallence electrons

C. they form crystalline salts

D. their salts are soluble in water

E. they are highly reactive

What is the likely formula of compound formed between element M in group two and element X in group seven?

A. M₇X₂

B. M₂X

C. M₂X₇

D. MX₂

E. MX₆

''Equal volumes of all gases at the same temperature and pressure contain the same number of molecules'' is an expression of

A. Charles Law

B. Boyle's Law

C. Avogadro's Law

D. Graham's Law

E. Gay Lussac's Law

What volume of carbon (lV) oxide is produced at s.t.p. when 2.5g of CaCO₃ reacts with excess acid according to the following equation? CaCO₃ + 2HCI → CaCI2 +H₂O + CO₂ [CaCO₃ = 100; molar volume of a gas at s.t.p = 22.4dm³]

A. 11.20dm³

B. 5.60dm³

C. 2.24dm³

D. 0.56dm³

E. 0.28dm³

A solution of pH 7 is

A. acidic

B. neutral

C. concentrated

D. dilute

E. saturated

Which of the following equations represents a neutralization reaction?

A. CaCI₂ + 2HCI →CI₂ +CaCI ₂ + H₂O

B. Na₂O₂ + H₂SO₄ → Na₂SO₄ + H₂O₂

C. H₂SO₄ + KOH → KHSO₄ + H₂ O

D. 2Na + 2H₂O → 2NaOH + H₂

E. CuSO₄ + 2NaOH → Cu(OH)₂+ Na₂SO₄