Explanation

(a)(i) X contains 40% carbon, 6.67% hydrogen, the rest being oxygen. To determine the empirical formula of X

(i) Percentage oxygen = 100 – (40 + 6.67) = 53.33%

C : H O

40 6.67 53.33

12 1 16

3.33 6.67 3.33

1 2 1

Ratio

Empirical formula is CH\(_2\)O

(ii) Molecular formula of X if its relative molecular mass is 60. (CH\(_2\)O)\(_n\) = 60;

(12 + 2 + 16)\(_n\) = 60 ;

30n = 60 ; n = 2

Molecular formula is C\(_2\)H\(_4\)O\(_2\)

(b) Y is an alkanoic acid with relative molecular mass is 74.

(i) The functional group in Y is –COOH/carboxyl group.

(ii) Esterification reaction

(iii) If Y is represented by C\(_n\)H\(_{2n+1}\)COOH; then 14n + 46 = 74, giving n = 2

(iv) 2C\(_2\)H\(_5\)COOH + 2Na –> 2C\(_2\)H\(_5\)COONa + H\(_2\).

(v) Compound Y in the same homologous series as X has a CH\(_3\)CH\(_2\)COOH relative molecular mass of 74. The boiling point of Y will be N higher. than 118° because in a homologous series boiling OH point increases with increase molar mass.

(c)(i) Fermentation is the breakdown of carbohydrates (sugars) to form ethanol (alcohol) and CO\(^2\) by the action of enzymes.

(iii) Yeast is added to glucose solution to make glucose ferment.

(iv) A tightly caked glass bottle filled to the brim with fresh palm wine shatters.on standing because CO\(^2\) is produced as the palm wine ferments. The gas causes pressure build-up which causes the bottle to shatter.

Correct Answer: B. climax

Correct Answer: B. 320Jkg^-1K^-1

Explanation

pt = mc\(\theta\)

C = \(\frac{pt}{m \theta}\)

= \(\frac{400 \times 1}{0.5 \times 2.5}\)

= 320Jkg^-1K^-1

Correct Answer: B. wind vane

Explanation

Wind direction is usually measured using a wind vane.

Correct Answer: B. growing of trade and commerce

Correct Answer: C. -3

Explanation

Using the remainder theorem, the remainder when a polynomial \(ax^{2} + bx + c\) is divided by \((x - a)\) is equal to \(f(a)\).

\(2x^{3} + 3x^{2} + qx - 1\) divided by \((x + 2)\), the remainder = \(f(-2)\)

\(\implies f(-2) = f(1)\)

\(f(-2) = 2(-2^{3}) + 3(-2^{2}) + q(-2) - 1 = -16 + 12 - 2q - 1 = -5 - 2q\)

\(f(1) = 2(1^{3}) + 3(1^{2}) + q(1) - 1 = 2 + 3 + q - 1 = 4 + q\)

\(4 + q = -5 -2q \implies 4 + 5 = -2q - q = -3q\)

\(q = -3\)

Explanation

According to the Muslim understanding, the Qur’an was revealed to the Prophet Muhammad over 23 years, from the age of 40 to his death at the age of 63. Over those 23 years, he received the revelation from God in a number of ways. Most commonly, it was spoken to him directly by the Angel Gabriel, but at other times it came during his dreams, and on a number of occasions, it even came to him directly from God, and he experienced this as the sound of a heavy bell, after which the words of the revelation were made clear to him.

Throughout those 23 years, the Prophet endeavoured to share the revelation with those around him as soon as it came. He did this verbally, as he couldn’t read or write, but he strongly encouraged others around him to write down the revelation, as well as memorise it. This was the basis of how Muslims believe the Qur’an became preserved, not purely through written or oral means, but with both strengthening the other. The companions around him constantly strove to memorise the verses, with many eventually memorising the entire book, and simultaneously wrote these verses on parchment, bone, wood, stone, basically whatever they had around them. Over time at least 65 companions functioned as scribes for the Prophet , who eventually established a school in Madinah dedicated to teaching 900 of his companions to read and write.

However, the dialect of the Quraishi tribe that the Prophet spoke in was not the only dialect of the Arabian peninsula, and as the religion was adopted by a growing number of tribes, they began to struggle with understanding the Qur’an. To overcome this, the Prophet was given permission to teach the Qur’an in 7 of the main dialects in the region, allowing the message to be understood more widely. These dialects didn’t affect the written records, as they were only different when the Qur’an was actually vocalised.

This was the state of the Qur’an at the death of the Prophet . Hundreds of companions who had memorised the complete Qur’an in 7 official dialects, all of which were considered valid ways of reciting the Qur’an, as well as an incredible amount of written records that were held by the Prophets companions throughout Madinah and beyond. The placing of each verse within each chapter had been established by the Prophet , but because each chapter functions as an independent unit, the companions had different ways of ordering the chapters themselves within the book as a whole.

Correct Answer: C. fixed cost and variable cost

Correct Answer: A) Moses was a great prophet who led Israel out of Egypt

Explanation

The question is asking how Moses was a prototype of Jesus Christ. A prototype is an early or preliminary version of something that serves as a model or example for future versions.

Moses was a great prophet who led the people of Israel out of Egypt and he is considered to be one of the most important figures in the Old Testament. In this way, he was a prototype of Jesus Christ.

As a prophet, Moses was able to communicate with God and receive divine instructions, which he then conveyed to the people of Israel. Similarly, Jesus Christ was also a prophet who communicated with God and taught his followers about God's will.

In addition, both Moses and Jesus were leaders who helped to guide their people towards salvation. Moses led the Israelites out of slavery in Egypt and towards the promised land, while Jesus led his followers towards eternal life through his teachings and sacrifice on the cross.

While Moses did not die a natural death, this is not the main reason why he was a prototype of Jesus Christ. Moses did appear with Elijah to Jesus on the Mount of Transfiguration, but this is not the main reason why he was a prototype of Jesus Christ either.

Therefore, option A is the correct answer to this question. Moses was a great prophet who led Israel out of Egypt and in this way, he served as a prototype of Jesus Christ.

Correct Answer: D) level of oxygen reduces