WAEC 2016 May/June 100% Correct Chemistry ,Essay,Theory (Obj), Question And Answers

CHEMISTRY OBJ: 1-10: CAACABCDBC

11-20: BABAADBDCA

21-30: BCCAABCDCB

31-40: ABCBCCCBBC

41-50: ABDBBBAABB

(1a) Nucleons is the sum total of neutrons and protons in the nucleus of an atom. It is the molecular weight of an atom. (1b) Graham ‘s law of diffusion states that at a constant temperature and pressure , the rate of diffusion of a gas is inversely proportional to the square root of it density (1c) Because when aluminum is exposed to moist air, a thin continuous coating of aluminum oxide is formed , which prevents further attack of the aluminium by atmospheric oxygen and water or steam under normal conditions (1d) (i) electron affinity (ii) electronegativity (iii) ionization energy (1e) (i) the molecule of real gases occupies space and there are forces of the attraction between them (ii) real gases do liquefy when their temperature droops. (1f) (i) used in separation of different component of crude oil . (ii)it is used for separating acetonic from water (iii) it is used for obtaining different gases from air for industrial use . (1g) (i) concentration of ions in electrolyte (ii)the nature of the electrode (iii)the position of ions in the electrochemical series (1h) (i) substitution reaction (ii)addition reaction (1i) (i) carbon dioxide (ii) water vapour (iii)carbon monoxide (1j) (i) centrifugation (ii)sieving (iii)evaporation to dryness =================================

(2ai) Isotopy (2aii) They have the same atomic number but different mass number (2aiii) -Chlorine -Carbon -Oxygen

(2aiv) PHYSICAL PROPERTIES -Metals are malleable while non metals are not malleable -Metals are ductile while non metals are not ductile -Metals are sonorous while non metals are not sonorous -Metals have high densities while non metals have low densities

CHEMICAL PROPERTIES -Metals are reducing agent while non metals are oxidising agent -Metals form basic oxide while non metals form acidic oxide -Metals lose electron while non metals gain electrons (2bii) I-Al2O3 -ZnO

II-CaH2

III-CaCO3

IV-CaCl2

-NaCl (2ci) -They have variable oxidation state -They have partially filled d-orbital -They have typical metallic properties -They have tendency to form complex ions

(2cii) The d orbital is completely filled (2d) 106g of Na2CO3-84g of mgCO3 xg of Na2CO3-3.36 of mgCO3 xg=(106*3.36)/84 =356.16/84 x=4.24g ================================== (3ai) This is the existence of compounds with the same molecular formular but with different structural formular (3aii) I-Tertiary alcohol II-primary alcohol III-secondary alcohol (3bi) I-CH3CH2COOK + H2 II-CH3CH2COOC4H9 + H2O III-CH3CH2CH2COOH (3bii) I-Sodium propanoate II-Butylpropanoate III-Butanoic acid (3c) 7.0g of R = 2.24dm^3 xg of R = 22.4dm^3 x=(7.0*22.4)/2.24 =70.0g of R (3ci) TABULATE |C |H % by mass |85.7|14.3 atomic mass|12 |1 mole ratio|85.7/12|14.3/1 =7.14|14.3 Divide by smallest=7.14/7.14|14.3/7.14 =1|2 Empirical formular=C1H2=CH2 (ii)Molecular formular (CH2)n=70 (12+2)n=70 14n=70 n=70/14=5 Molecular formular=(CH2)5=C5H10 (3d)diagram ============================

(4ai) calcium chloride, CaCl2 (4aii) to the unknown substance in a gas jar, add small quantity of lime water. if the gas is carbon(iv)oxide, it turns lime water milky while carbon (ii) oxide has no effect

(4bi) oxygen is releasedf abundantly from air and nitrogen is produced by the reaction of potassium trioxonitrate(v) with concentrated hydrochloric acid (4bii) oxygen gas rekindle a lighted splint while nitrogen does not (4ci) Bauxite is preferred because it is readily available in the earth crust (4cii) -trioxosilicate(iii) -carbon(iv)oxide (4ciii) -it helps to purify the bauxite (4civ) it is difficult to extract aluminium by chemical reduction of aluminium oxide in amphoteric (4cv) AL2O3+NaOH=>Na2O + Al+ H20 ==================================== (5ai ) Na2S2O3 ===> 2+2x+6=0 2x=6-2=4 X=4/2 X=2 The oxidation number of sulphur is 2 (5aii) Rhombic & monoclinic (5aiii ) -Both are tetravalent -both are allotrope of carbon (5bi) CO2 & Chloroflorocarbon (5bii) There is increase in sun radiation reaching the earths surface ie Global warming (5biii ) ThunderStorm (5iv) I 2KNo3 —-> 2KNO3 + O2 II AgNo3 —> 2Ag + 2NO (5ci) Calcium chloride in a solution can give rise to crystal using filteration & evaporation to dryness . The sol is filtered into filtrate & residue b4 evaporation to dryness takes place .

(5cii) – Because of presence of hydrogen bonding in NH3 -Because Iodine as higher molecular mass than chlorine

(5di) Mol of Nacl = Mass/MM = 5.85/58.01 = 0.1mol From the equation 2mol of Nacl gives 2mol of HCL, 0.1mol of Nacl gives 0.1mol of Hcl Vol of Hcl = 0.1 x 22.4 = 2.24mol/dm^3

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Waec 2016 May/June 100% Correct English Language Essay,Obj,Oral test Question And Answer

ENGLISH ORAL OBJ

1BCBAACBBCD

11ABCCCBACCB

21CABDBDDACD

31CDCADBADAC

41CCCBAABAAD 51BCACAACBCC

Verified Eng Obj

1CADCBCCCAD

11DBDBDDDABA

21BBDACABBBC

31BAABBBBDAB 41DBAAABABCC

51ABCBBBBCCB

61DBDCCADABB

71CDABBDACDD

(6a) the writer’s father warned them for the unsafe incidences that happen in the community lately.

(6b)The quotation is a “stone thrown from ours”

(6c)the toys were discovered for he has spotted them before and the injury by the writer

(6d)he jumped down unbalancedly

(6e)the father did not believe his son could be outside at that time despite his fore warning

(6f) (i)Noun phrase (ii)it is the object of the verb “raised”

(6g) (i)simile (ii)fast

(6h) (i)short time ago (ii)sweet (iii)quality (iv)moving closed (v)saw (vi)confirm

7a) The factors that have prompted the rapid increase in the world population are: -Improvement in medical services which have reduced deaths rates -The spread of education has created a wide level of awareness about human welfare and health -There is improvement in nutrition in nutrition due to modern agricultural research -Adequate security in place to check wars annd riots

7b) What are likely to follow the continuing population growth are: -Over population,the planet earth maybe too small to host human beings -Too many people will contribute to environmental pollution ++++++++++++++++++++++++++++++ I PITY THOSE THAT COPY WRONG ANSWERS FROM OTHER SITES. USE OURS IF YOU WERE DIRECTED HERE WE CONFIRM BEFORE DISTRIBUTION.

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Waec 2016 May/June 100% Correct Government Obj And Theory Answer

GOVT OBJ:

1-10: DBDBDADBDB

11-20: ADCDADCBAD

21-30: ADAACCCBAB

31-40: ADDCDDDDBD

41-50: DBBDADCDCC

(10a) National interest is by definition the decision and desires of a country,the purpose of which the nation interacts with other nations of the world. It includes what a country wishes to gain by interacting with other countries of the world. It has a lot to do with the gains of a country in her foreign policy with other countries

(10b) -Independence of African states -Respect for territorial integrity -Peaceful resolution of crises -Friendship and cooperation with other nations of the world

6) i) Decentralized administration. ii) The village was the highest unit of administration. iii) Existence of village assembly (Oha-na-eze/Umunna).

iv) The village priest/diviner wielded great deal of religious and judicial powers.

v) Significant position of age – grades. vi) The family heads played important role in the administration of the village

9a) i)To promote the unity sovereignty and territorial integrity of nigeria ii)To provide food & shelter for a better standard of living iii)To enhance the rule of law equal justice

9b) i)Government Reimbursement ii)Fund raising through party members

8) i)military and technical aid: some former territories especially d french territories, receives military and technical aid from their former coloniaal masters ii)trade relations: this was established with britain and france. iii)Uniform civil service: the civil service was developed along that of the British and french colonies. iv)Common legal system: there was the development of a common legal. System among the colonial system v)the emergence of the press: another impact of colonialism was the emergence of the press. The press developed and became the mouthpiece of the people in the struggle for political independence

7a) i)Ivory coast ii)Benin republic iii)Senegal =================

1a) Racism can be defined as a form of government headed by a dictator, where government has a total say over all activities in the state and personal liberties are denied the people.

1b) i) The state economy is highly centralised ii) Superiority of the state iii) Autocratic tendency iv) Refuse to submit to international conventions

3) i)decrees: military regime promulgates decrees that cannot be challenged in the law court ii)political interference: d decisions of the court may be unduly influenced by the other arms of govt iii)political appointments: the appointments of judges Is influenced by the executive arm of govt. iv)bribery and corruption: it lead to lack of confidence in d judiciary. v)disrespect of court decision/orders: sumtyms d decision of the law courts are disobeyed by the executive. ==================

1b) i) State-worship, meaning that state is supreme and everything else is subservient to the state.

ii) Leader-worship which means the leader is the all- powerful man and everybody should abide by him. iii) War-worship meaning that war is inevitable and peace in politics is seldom to be found. iv) Anti-communism and opposition to democracy. Fascists were anti-communists because the communists were internationalists, while Fascists glorified the nation ++++++++++++++++++++++++++++++

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Bayern draw enough to seal progress to semi final

The pair hit either side of half time to put Die Roten back in charge after Raul Jimenez had opened up the tie, and the Bavarians finally booked a last-four spot Bayern Munichhad Arturo Vidal and Thomas Muller to thank as they fought to a 2-2 draw with Benfica, a result which was enough to send them through to the Champions League semi-final.

Vidal had scored the winner when the sides met in Munich last week and was on hand to cancel out Raul Jimenez's opener during the first half of a 2-2 draw in Lisbon on Wednesday.

Benfica soaked up sustained Bayern pressure in the early stages at Estadio da Luz, but broke the deadlock against the run of play through a Jimenez header. Vidal's powerful leveller provided Pep Guardiola's men with a healthy cushion to defend, leaving Benfica needing two goals by the end of 90 minutes to progress. Thomas Muller put the match to bed after the break, with his goal effectively ending home hopes of a maiden last-four appearance of the Champions League era. Talisca scored from a 76th-minute free-kick to reduce the deficit, but the damage had already been done, with Bayern now facing the possibility of a clash with Manchester City – Guardiola's future employers – in the last four. Bayern's first-leg advantage was almost wiped out within three minutes, when Joshua Kimmich conceded a soft free-kick in a dangerous position and Eliseu's low drive ran wide via a deflection off the wall. The visitors survived that early scare and started to exert some pressure, but struggled to test Ederson in the Benfica goal.

Muller turned wide from a Philipp Lahm cross after 19 minutes as Bayern continued to dominate possession, while David Alaba's skewed effort moments later only served to increase German frustrations.

Vidal failed to get enough power on his header from a lofted Thiago Alcantara ball into the box, with Ederson eventually able to gather, and Bayern were ultimately made to pay for their lack of final product by a great demonstration of vision from Eliseu.

The 32-year-old sent a high ball forward for the advancing Jimenez to head home, with Bayern goalkeeper Manuel Neuer uncharacteristically wayward in his attempts to punch clear.

Benfica could easily have been two up three minutes later, but Jimenez prodded straight at Neuer from the centre of the box. And Bayern punished that squandered opportunity when an unmarked Vidal rifled home on the half-volley from the edge of the box after Ederson had inadvertently parried a cross into his path.

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Griezmann sends Barcelonal crashing out of Uefa Champions league

The France international netted a header and converted a late penalty to reverse last week's 2-1 defeat and send his side through to the semi-finals of the Champions League Barcelona's season unravelled further in controversial fashion after the holders were knocked out of the Champions League by Atletico Madrid on Wednesday, with Antoine Griezmann's double securing passage to the semi-finals with 2-0 win at the Vicente Calderon. Heading into stoppage time and searching for the goal that would have forced an extra 30 minutes, Barca were incensed not to receive a penalty when Andres Iniesta's shot struck the arm of Atletico captain Gabi just inside the box, with the referee instead awarding a free-kick which Lionel Messi hit over.

Luis Enrique's men had led 2-1 from the first leg but ultimately failed to cope with the intensity of an Atletico side who are also just three points behind them in La Liga and will be buoyed by this scalp as they seek to heap added misery on to their Catalan counterparts domestically.

Barcelona's willingness to sit on that slender first-leg lead led to a cagey and tense first half-hour, but Atletico broke through with 36 minutes on the clock, as Griezmann nodded in to spark wild celebrations.

Dogged Atletico held firm for the remainder of the half and went desperately close to a second soon after the break, but Lucas Hernandez's header was kept out by the crossbar.

Barca soon began to exert some control, keeping Atletico penned back, but Jan Oblak had little trouble keeping Luis Suarez at bay with their best chance just after the hour mark. Atletico were forced to withstand significant pressure during the final stages, but Diego Simeone's men held on in typical fashion and then netted a second on the break as Iniesta's handball allowed Griezmann to convert from the spot with two minutes remaining. Referee Nicola Rizzoli then provoked a furious reaction from Barca with his decision to award only a free-kick for Gabi's handball, and the result means Atletico have knocked Barca out in the quarter-finals of this competition in two of the past three seasons, while they gain further psychological advantage in their quest to chase down Barca's slender lead in the league with just six games to go.

Urged on by a raucous atmosphere at the Vicente Calderon, Atletico began proceedings with great urgency, pouring men forward quickly and in numbers. It took just seven minutes for the hosts to create the first chance and they ultimately let Barca off the hook, as the unmarked Griezmann headed straight at Marc-Andre ter Stegen. Barca's terrifying attack of Messi, Neymar and Suarez were being kept quiet, but the away side did get to grips with Atletico's intense pressing, resulting in the two sides cancelling each other out in midfield for long periods.

Atletico's patience and intensity paid off nine minutes before the break, though, as Griezmann rose to meet Saul Niguez’s delightful cross and sent a fine glancing header past the helpless Ter Stegen. Simeone's men could have added a second just before the interval, but Yannick Ferreira Carrasco was thwarted by Ter Stegen after single-handedly leading a breakaway.

Barca initially struggled to mount a response after the break and Atletico went mightily close to increasing their lead, as Lucas' looping header bounced back off the bar in the 54th minute.

A crucial block from Gabi six minutes later prevented Suarez a simple tap-in, but the occasion marked an improvement from the visitors.

Oblak was their saviour in the 66th minute, as the goalkeeper got himself in the way of Suarez's effort after the Uruguayan expertly turned his compatriot Diego Godin on the edge of the area.

Wave after wave of Barca attacks were halted by the home defence during the final 20 minutes, as the reigning champions continued to be frustrated, with Messi kept particularly quiet. Barca threw everything at Atletico in desperate fashion for the final 10 minutes, but it was the home side who were left jubilant.

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Waec 2016 May/June 100% Correct Chemistry (pratical Alt A) Question And Answers

1) TABULATE Volume of pipette Burette reading(cm3)|Rough titre(cm3)|First titre(cm3)| Second titre(cm3) Final reading(cm3)|20.00|19.60|19.60 Initial reading(cm3)|0.00|0.00|0.00 Volume of acid used|20.00|19.60|19.60 Average titre=(19.60+19.60)/2 cm3 =39.20/2 cm3 =19.60cm3 Equation=>2MnO4^-+5C2O4^2-+16H^+->2NA^2++8H2O +10CO2

1bi) Conc of B in mol/dm3 CaVa/CbVb=Na/Nb (0.05*19.6)/(Cb*25.0)=5/2 5*Cb*25=2*0.05*19.6 Cb=(2*0.05*19.6)/(5*25)=1.96 Cb=0.0157mol/dm3 Cb=0.016mol/dm3

1bii) Conc in B in g/dm3 =0.0157*158 =2.4806g/dm3 =2.481g/dm3

3a) i)Simple distillation-wide boiling point difference between constituent liquid ii)Chromatography-Relative migration of constituents of mixture over an absorbent or rf-value difference of constituents of mixture

iii)Fractional distillation-Close boiling point between constituent liquid

3b) i)For easy identification of the end point ie the point of complete titration where the colour change is observed

ii)For accurate titre value ie to minimize the error margin

3c) C1=2.5mol/dm3, V1=?,C2=0.20mol/dm3,V2=500cm3 C1V1=C2V2 V1=C2V2/C1 V1=(0.20*500)/2.5 V1=100/2.5 V1=40cm3

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Hat-trick hero Ronaldo puts Real through to Semi final

The Portuguese striker levelled the game in the first half with a close-range finish and a header, and later ended the Germans' hopes by squeezing a free-kick through the wallA brilliant hat-trick from Cristiano Ronaldosaved Real Madrid's Champions League campaign, as the Spaniards battled back to down Wolfsburg3-0 and progress to the semi-finals.

Madrid appeared to have a sizeable task in front of them having lost the first leg in Germany 2-0 but were rescued in stunning fashion as Ronaldo continued his magnificent goalscoring form in the Champions League.

The former Manchester United forward netted two goals in the space of 90 seconds to bring Madrid level in the tie, before completing his treble and the turnaround with 13 minutes remaining.

Ronaldo halved the aggregate deficit with a composed 15th-minute finish and just one minute and 26 seconds later Madrid were all square as he headed home Toni Kroos' corner.

Wolfsburg did not lie down following that devastating spell and threatened on multiple occasions to turn the tie back in their favour. But Ronaldo refused to be denied and capped a stunning individual performance in fitting fashion with a sublime free-kick that marked his 16th Champions League goal of the season and kept Madrid's hopes of an 11th European crown very much alive.

Madrid unsurprisingly made the more aggressive start to proceedings, Sergio Ramos hitting the top of the crossbar with a header from Kroos' corner.

And just as Wolfsburg appeared to be weathering the early storm Ronaldo struck with a cool close-range finish after Dani Carvajal had found the Portugal forward at the second attempt with a cross from the right.

Vieirinha was forced to turn another Carvajal cross aimed at Ronaldo behind for a corner as Madrid went in search of a second, which arrived from Kroos' subsequent delivery.

Wolfsburg failed to track Ronaldo at the near post and he made no mistake in glancing Kroos' ball into the bottom-right corner to level the tie.

Luiz Gustavo forced Keylor Navas into his first save of the game with a long-range effort before Karim Benzema tested Diego Benaglio at the other end as the contest became more open.

But Wolfsburg's hopes were dealt a significant blow in the 31st minute when Julian Draxler limped off to be replaced by Max Kruse. Despite that setback, the visitors twice went close to regaining the aggregate lead shortly after.

Luiz Gustavo's swerving strike from distance drew a fine acrobatic save from Navas and Ramos produced a vital block to prevent Bruno Henrique from finding the net.

For all their spirit, Wolfsburg almost contributed to their own downfall in the 59th minute when Benaglio had to react quickly to prevent Josuha Guilavogui from turning Luka Modric's cross into his own net. And the visitors were fortunate not to see Ramos complete the comeback as his header from Kroos' corner struck the inside of the post, with Benaglio then showing the presence of mind to trap the ball between his legs before it crossed the line. Bruno Henrique was forced off following a collision with Marcelo - with Daniel Caligiuri coming on in his stead - in another dent to Wolfsburg's cause and soon afterwards they were behind for the first time in the tie. Luiz Gustavo received a yellow for hacking down Modric on the edge of the area, and Ronaldo took full advantage of a perfectly positioned free-kick with a dinked effort through the wall. Benzema and Jese Rodriguez each went close late on but Madrid were not made to pay for those missed chances as Wolfsburg failed to net the away goal that would have spoiled the party for Ronaldo.

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