Correct Answer: A. terms of trade

Correct Answer: C. enigma

Explanation

The word 'enigma' has a different stress pattern compared to the other words. The primary stress is on the second syllable, while the other words have their primary stress on the first syllable.

Correct Answer: C. packaging

Correct Answer: C. consume more of commodity X

Explanation

A rational consumer should consume more of commodity X when the marginal utility from the consumption of commodity X (Mux) is greater than the price commodity X (Px). This is because the consumer is getting more satisfaction from consuming each additional unit of commodity X than they are paying for it. As a result, the consumer should continue to consume more of the commodity until the marginal utility is equal to the price.

Correct Answer: C. Allowed the man to carry his pallet

Correct Answer: D. UPN

Correct Answer: B. onto

Explanation

The function \(y = g(x)\) is one- to- one but \(z = h(y)\) is not one- to- one but onto.

\(\therefore h(g(x)) = onto\)

Correct Answer: C. Uzziah of Judah died

Correct Answer: C. 4.6g

Explanation

(a)(i) - Covalent compounds contain only molecules while electrovalent compounds do not contain molecules

- Covalent compounds usually dissolve in covalent organic Products compounds but not in water but electrovalent compounds are soluble in water

- Covalent compounds are usually volatile with low melting and boiling points but electrovalent compounds usually have high melting and boiling points.

(ii) \(_{12}\)K has an electronic structure of 1s\(^2\)2\(^2\)2p\(^6\)3s\(^2\); L has the structure of 1s\(^2\)2s\(^2\)2p\(^4\); belongs to group II and L to group VI

(iii) Alkali metal M cannot be extracted by reduction of the oxide with oxide coke because of its high stability and reactivity.

(b)(i) The half-life of a radioactive element is the time it takes for one half of any quantity of a radioactive molecule to decay. It is therefore also equal to the time for the amount of the radioactive nuclide present to fall from one half to one quarter, from one quarter to one eight, etc.

(ii) The radioactive isotope normally used in dating archaelogical specimens is carbon - 14.

(iii) \(^{28}_{13}Al\) -> \(^{28}_{14} Si\) + \(^0_{-1}Q\)

(c)(i) - electropositive

- form electrovalent chlorides

- Replace the hydrogen in acid if more electropositive than hydrogen

-Form metallic hydrides/ionic hydrides.

(ii) Duralumin is preferred to steel in aircraft manufacture because duralumin is lighter and more resistant to corrosion.

(iii) The ability of metals to be hammered into thin sheet is described as malleability.

(iv) To calculate the number of mole of electrons involved in the oxidation of 2.8g of iron filing to Fe\(^{2+}\) + Fe —> Fe\(^{2+}\) + 2e\(^{-}\) ; 56g of Fe loses 2 mole of electrons.

2.8 of Fe would lose \(\frac{2.8 \times 2}{56}\) = 0.10 mole