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  Classification of Matter       All the objects that we see in the world around us, are made of matter. Matter makes up the air we breathe, the ground we walk on, the food we eat and the animals and plants that live around us. Even our own human bodies are made of matter! Different objects can be made of different types of materials (the matter from which objects are made) . For example, a cupboard (an object) is made of wood, nails, hinges and knobs (the materials). The properties of the materials will affect the properties of the object. In the example of the cupboard, the strength of the wood and metals make the cupboard strong and durable. It is very important to understand the properties of materials, so that we can use them in our homes, in industry and in other applications. Some of the properties of matter that you should know are: Materials can be strong and resist bending (e.g. bricks, rocks) or weak and bend easily (e.g. clothes) Materials that conduct ...

 1. Can you pass me a plastic knife?   A. PLAS-tic  B. plas-TIC 2. I want to be a photographer .   A. PHO-to-graph-er  B. pho-TO-graph-er 3. Which photograph do you like best? A. PHO-to-graph B. pho-TO-graph 4. He was born in China .   A. CHI-na  B. Chi-NA 5. Whose computer is this?   A. com-PU-ter  B. com-pu-TER 6. I can't decide which book to borrow.   A. DE-cide  B. de-CIDE 7. Couldn't you understand what she was saying?   A. un-DER-stand  B. un-der-STAND 8. Voting in elections is your most important duty.   A. im-POR-tant  B. im-por-TANT 9. We had a really interesting conversation .   A. con-VER-sa-tion  B . con-ver-SA-tion 10. How do you pronounce this word?   A. PRO-nounce  B. pro-NOUNCE Correct answers: 1. PLAS-tic 2. pho-TO-graph-er 3. PHO-to-graph 4. CHI-na 5. com-PU-ter 6. de-CIDE 7. un-der-STAND 8. im-POR-tant 9. con-ver-SA-tion 10. pro-NOUNCE Rules of stress: 1. Stress the f...

Questions 1. When a p-n junction is under reverse bias mode, the width of the depletion region will be increased. Which of the following statements is true? A. The applied voltage moves the electrons from n-type region to p-type region. B. The applied voltage moves the holes from p-type region to n-type region. C. The applied voltage drives the electrons towards n-type region. D. The applied voltage drives the holes towards n-type region. Explanation: Under reverse bias mode, the electrons in the n-region are pulled away from the depletion region, leaving more immobile positive ions in the region. In other words, the electrons are driven towards the n-region. Answer is C 2. Which statement about conduction of electricity in semiconductors is correct? A. The presence of impurities in a semiconductor is used to decrease its resistance. B. In a semiconductor, there is a large energy gap between the conduction and valence bands. C. At low temperatures, free electrons are found both in the ...

  1. Which one of the following is NOT a mixture? A. Air B. Sugar C. Paint D.  Crude oil 2. Oil and water may be separated by using? A. a separating funnel B. a Liebig condenser C. chromatography paper D. a filter funnel 3. Air is a mixture of A. liquids B. solids C. gases D. liquids and gases 4. In a coffee machine, the ground coffee is separated from the coffee solution by using A. toilet paper B. filter paper C. sand paper D. tissue paper 5. Which one of the following techniques would best be used to separate soil and water? A. Decanting B. Filtration C. Fractional distillation D. Chromatography 6. This is a simple method of separating an insoluble solid from a liquid.  A. Filtration  B.  Distillation  C. Evaporation  D. Decantation 7. In the process of evaporation, which one of the following pieces of laboratory apparatus would NOT be used?  A. wire gauze  B. evaporating basin  C. filter funnel  D bunsen burner 8. Which one of t...

1. The nucleus of an atom consists of A. electrons and neutrons B. electrons and protons C. protons and neutrons D. All of the above 2. The most electronegative element among the following is A. sodium B. bromine C. fluorine D. oxygen 3. The metal used to recover copper from a solution of copper sulphate is A. Na B. Ag C. Hg D. Fe 4. The metallurgical process in which a metal is obtained in a fused state is called A. smelting B. roasting C. calcinations D. froth floatation 5. The most commonly used bleaching agent is A. alcohol B. carbon dioxide C. chlorine D. sodium chlorine 6. The most malleable metal is A. platinum B. silver C. iron D. gold 7. The most abundant rare gas in the atmosphere is A. He B. Ne C. Ar D. Xe 8. The metal that is used as a catalyst in the hydrogenation of oils is A. Ni B. Pb C. Cu D. Pt 9. The heat required to raise the temperature of body by 1 K is called A. specific heat B. thermal capacity C. water equivalent D. None of the above 10. The nucleus of a hydroge...

-PROBABILITY = Number of POSSIBLE EVENT Number of TOTAL OUTCOME   Question 1 Teams P and Q are involved in a game of football. What is the probability that the game ends in a draw? Options A) ⅔ B) ½ C) ⅓ D) ¼ Solution: In a football game, one team either wins or there is a tie. This means there are three possible outcomes: a win, a loss or a draw. Therefore, the probability of a draw is ⅓ The correct answer is C. Question 2 Given distribution of color beads: blue, black, yellow, white and brown with frequencies 1, 2, 3, 4 and 5 respectively. Find the probability that a bead picked at random will be blue or white. Options A) 7/15 B) 2/5 C) 1/3 D) 1/15 Solution: Total number of beads = 15. Number of white beads = 4. ⇒P(white) = 4/15 Number of blue beads = 1. ⇒P(blue) = 1/15 P(white or blue) = P(white) + P(blue) =5/15 🔶P(white or blue) = ⅓ The correct answer is C. Question 3 A die is rolled, find the probability that an even number is obtained. Options A. ⅙ B. ¼ C. ⅓ D. ½ Solution...

  30 Examples To Help You Master Concord What is concord in writing? We have put together this list of 30 examples to help you master concord. What Is Concord? When we use the word ‘concord’ in everyday speech, it means ‘agreement or harmony between people or groups’ (Oxford Dictionary). When we use the word in the context of grammar, it has a similar meaning: grammatical agreement between two parts of a sentence. An important language skill to master is subject-verb concord. The Basics Of Concord Subject-verb concord is when the subject of a sentence and the verb of a sentence agree. Simply,  if the subject of the sentence is singular, the verb must be singular. If the subject of a sentence is plural, the verb must be plural. Here are 30 Examples To Help You Master Concord 1. The pages (subject) is (verb) held together by a staple. 2. The pages (subject) are (verb) held together by a staple. Number 2 is correct, because the subject, ‘pages’, and the verb, ‘are’, are both pl...

  Question 1 Read the passage below carefully and answer the question that follows. How can people be sure that they are truly marrying people with whom they are truly compatible? One way is by taking time to get to know the other person. Researchers have found that couples seem to go through three stages in this process. First, each person tries to measure his or her good and bad qualities against those of the other person. People tend to be drawn to others who seem to have about the assets and liabilities they themselves possess. Second, people look for compatible beliefs, attitudes and interests to support the initial attraction. It is not until the third stage that people reveal to each other how they handle responsibilities, react to disappointments and cope with a wide variety of situations. The key to compatibility is for the couple to be sure that they have arrived at this last stage before they think about marriage. Such people are less likely to be unpleasantly surprised ...

From the alternative provided in the question below select the one which is most appropriately completes the sentence: 1. Had he known that it would rain, he ________ his umbrella with him. A) would have taking B) was going to take C) would be taking D) would have taken E) would take Explanation: After have, has and had, the verb that will follows must be past participle. The correct answer is D. 2 . Omeime was taking his dog for a walk when the dog suddenly _______ from its chain and escaped A) broke through B) broke lose C) broke even D) broke loose E) broke away Explanation: Loose is different from lose. Loose in this sense mean to break free from something, then lose means to have lost something, but here the dog loosed from the chain, i.e. to break free from the chain . The correct answer is D. 3 . I was still sleeping when the national news ________ this morning A) were broadcast B) were broadcasted C) was broadcast D) was broadcasted E) were being broadcasted Explanation: The re...

  A hot potato Speak of an issue (mostly current) which many people are talking about and which is usually disputed A penny for your thoughts A way of asking what someone is thinking Actions speak louder than words People's intentions can be judged better by what they do than what they say. Add insult to injury To further a loss with mockery or indignity; to worsen an unfavorable situation. At the drop of a hat  without any hesitation; instantly. Back to the drawing board When an attempt fails and it's time to start all over. Ball is in your court It is up to you to make the next decision or step Barking up the wrong tree Looking in the wrong place. Accusing the wrong person Be glad to see the back of Be happy when a person leaves Beat around the bush Avoiding the main topic. Not speaking directly about the issue. Best of both worlds All the advantages. Best thing since sliced bread A good invention or innovation. A good idea or plan. Bite off more than you can chew To take on...

  QUESTIONS 1. WISTFUL A) Conversant  B) Esoteric  C) Forlorn  D) Blithe  Explanation: WISTFUL - having or showing a feeling of vague or regretful longing. Blithe - happy or carefree. Hence, Wistful is the antonym of Blithe. 2. OFFICIOUS A) Repose  B) Unofficial  C) Indifferent  D) Attached  Explanation: Officious - intrusively enthusiastic in offering help or advice; interfering. Indifferent - showing no concern in attitude or action. Hence, Indifferent is the antonym of Officious. 3. OUTLANDISH A) Quirky  B) Atypical  C) Conventional  D) Crotchety  Explanation: Outlandish - strange and unusual. Hence, Conventional is the antonym of Outlandish. 4. Sanctimonious A) Devout  B) Impious  C) Empirical  D) Maudlin  Explanation: Sanctimonious means making a hypocritical show of religious devotion, piety, righteousness. Devout means having or showing deep religious feeling or commitment. Impious means s...

  List of Synonyms Come — advance, approach, arrive, near, reach Go — depart, disappear, fade, move, proceed, recede, travel Run — dash, escape, elope, flee, hasten, hurry, race, rush, speed, sprint Hurry — rush, run, speed, race, hasten, urge, accelerate, bustle Hide — conceal, cover, mask, cloak, camouflage, screen, shroud, veil Move — plod, go, creep, crawl, inch, poke, drag, toddle, shuffle, trot, dawdle, walk, traipse, mosey, jog, plug, trudge, slump, lumber, trail, lag, run, sprint, trip, bound, hotfoot, high-tail, streak, stride, tear, breeze, whisk, rush, dash, dart, bolt, fling, scamper, scurry, skedaddle, scoot, scuttle, scramble, race, chase, hasten, hurry, hump, gallop, lope, accelerate, stir, budge, travel, wander, roam, journey, trek, ride, spin, slip, glide, slide, slither, coast, flow, sail, saunter, hobble, amble, stagger, paddle, slouch, prance, straggle, meander, perambulate, waddle, wobble, pace, swagger, promenade, lunge Do — execute, enact, carry out, finish...

  The amount of energy released when 0.5kg of uranium is burnt completely? Options: A) 1.5 x 10^ 8 B) 6.0 x 10^ 16 C) 4.5 x 10^ 16 D) 1.5 x 10^ 16 Solution: E= Mc^2 E= (0.5 x 3x10^8)^2 E = 4.5 x 10^16 Correct answer is C

  Question: The number of nonbonding (lone) pairs in a water molecule is __________. Options: a. one b. two c. three d. four Explanation : In a water molecule, even though it has 2 bonding pairs (2 Hydrogen atoms attached to Oxygen atom), it does not have a linear geometry. The geometry of water is known as bent. It has a bent geometry due to the 2 lone pairs present in the Oxygen atom (central atom) that results in a repulsion to form a bent geometry. Again, the water molecule has 2 nonbonding (lone) pairs in the Oxygen atom (central atom). Lone pairs: A nonbonding(lone) pair is a pair of valence electrons that are not involved in any kind of bonding to any different atoms. Basically, it is an excess valence electrons that are usually represented by two dots in the central atom. The lone pair has a nucleophilic property and can undergo bond formation if there is an electrophilic compound present. The lone pair in the central atom can cause a change or shift in the orientation sinc...

The maximum kinetic energy of photoelectrons emitted from a surface when photons of energy 6 eV fall on it is 4 eV. The stopping potential in volts is : Option A. 2 B. 4 C. 6 D. 10 Correct answer is: B EXPLANATION Given, the maximum kinetic energy:  K max   = 4eV If V 0    be the stopping potential, then K  max  = eV o  ⇒ eV o  = 4eV  ⇒V o  =4V

 The process by which protons are converted into helium atoms with a tremendous release of energy is called? A) thermionic emission B) nuclear fission C) thermonuclear fusion D) photoelectric emission The correct answer is C. Explanation : Thermionic emission: thermally induced flow of charge Nuclear fission: nuclear reaction or a radioactive decay process Photoelectric emission: emission of electrons or other free carriers when light shines on a material

  A radioactive sample initially contains N atoms. After three half-lives the number of atoms that have disintegrated is A. N8 B. 3N8 C. 5N8 D. 7N8 Correct Answer: Option A Explanation N → N2 → N4 → N8