eCoaching | Online Home Tutors & Teachers
Question Options
The equation for the reaction between aqueous lead (II) nitrate and aqueous potassium iodide is shown Pb(NO3)2(aq) (colourless) +2Kl(aq) (colourless) ? PbI2 (S) (yellow) + 2 KNO3 (aq) (colourless) which method would be used to separte the product ? Chromatography, Crystallisation, distillation, filtration
A 25 cm3 sample of dilute sulphric acid contains 0.025 mole of the acid.what is the hydrogen ion concentration in the solution ? 0.25 mol /dm3, 0.50 mol /dm3, 1.00 mol /dm3, 2.00 mol /dm3
for which of the following can graphite be used ? as an abrasive only, as an abrasive and as an electrode, as an electrode and as a lubricant, as a l
The letter X,Y and Z represent different atoms 40/19X 39/19 Y 40/20 Z what can be deduced from the proton number and nucleous number X,Y and Z ? X and Y are the same element, X and Z are the same element, X has more protons then Y, Z has more
How does a magnesium atom form a bond with an oxygen atom ? By giving one pair of electrons to the oxygen atom, by sharing one pair of electron,both electron p
Element X and Y combine to form the gas XY2 what are X and Y ? Calisium , chlorine, Carbon ,hydrogen, Carbon , oxygen, Hydrogen , oxygen
Which of the following contains the same number of electrons as an atom of neon ? Cl-, Li, Li+, O2-
Which sulphide contains the greatest mass of sulphur in a 10 g sample ? NiS , 90, FeS2 ,120 , MoS2 ,160, PbS , 239
124 g of phosphorus vapour has the same volume as 71 g of chlorine at the same temperature and pressure What is the formula of a molecule of phosphorus ? P8, P4, P2, P
A piece of metal is to be electroplated.which set of condition gives the thickest plate ? A.c , low , short, d.c , high , long, a.c , high , short, d.c , low ,long
Rubidium is above sodium in the reactivity series what is formed when concentrated aqueous radium chloride is electrolysed? Chlorine , hydrogrn, Hydrogen , chlorine, hydration , chlorine, Rubidium , chlorine
Substance X libertes iodium from aqueous potassium iodide and decolourises acidified aqueous potassium manganate VII how is the behiour of X described ? as an oxidising agent only, as an oxiding agent nor a reducing agent, as a reducing agent only, as a
Salts are made by reacting acids and based is the titration method of preparation suitable? an insoluble acid with an insoluble base, an insoluble acid with insoluble base , a soluble acid wit
A black powder is burned in air the gas produced dissolved in water to form solution R the pH of R.the pH of r is closed to 7 the gas is readily absorbed in aqueous sodium hydroxise .what type of substance is present in solution R ? Strong acid, Strong base, Weak acid, Weak base
Which statement about the periodic table is correct : A melting point of the element increase down Group I, The reactivity of the element increases down G
In which process is a cataalyst not used ? The blast furance for the manufacture of iron, The contract process for the manufacture of sulphric
Why is cryolite Na3Alf6 used in the extraction of aluminum from aluminium oxide ? To dissolve aluminum oxide, To prevent the anode from burning away, To prevent the oxidation of alu
The carbonate of metal X is a white solid .it decomposes when heated .Carbon dioxide and a yellow solide and a yellow solide oxide are formed what is metal X ? Copper, Iron, Lead, sodium
An 80 cm3 sample of air is trapped in a syringe .The air is slowly passed over heated iron in a tube until there is no futher decrease in volume when cooled to the orignial temperature which volume of gas remains ? : 80 cm3, 64 cm3, 20 cm3, 16 cm3
in the Haber process , nitrogen and hydrogen react form ammonia what is the source of the hydrogen ? Air, Oil, Limestone, Sulphric acid
which reaction will not occur using cold dilute sulphric acid ? formation of copper (II) sulphate from copper (II) oxide, formation of copper (II) sulphate from cop
Why are catalytic converters fitted to car exhausts ? To decrease the amount of carbon dioxide emmitted, To decrease the amount of nitrogen oxide emmitted
why is carbon used in the purfication of drinking water ? disinfect the water, filter out solids, removes tastes and odour from the water, desalinates the wat
what is produced when ethanol is boiled with an excess of acidified potassium dichromate VI ? ethane, Ethanoic acid, ethene, ethyl ethanoate
when 1 volume of gas X react with exactly 5 volume of oxygen it form carbon dioxide and water only . What is the gas X ? methane, CH4, ethane, C2H6, Propane, C3H8, Butane C4H10
Amino acid are produced when protein are : hydrolysed, Oxidised, Polymerised, Dubstituted