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At higher temperatures, graphite has an intermolecular structure with immobile ions thus making it a poor conductor of electricity.
Drezline answered the question on October 10, 2018 at 11:55
- Which of the following is a non metal that remains liquid at room temperature?
A. Phosphorous
B. Bromine
C. Chlorine
D. Helium(Solved)
The answer is B.
Bromine has boiling point of 58.78 and has -7.2 melting point
Date posted: September 30, 2018. Answers (1)
- Which gas in the air make Brass get discoloured when they react?(Solved)
Which gas in the air make Brass get discoloured when they react?
Date posted: September 30, 2018. Answers (1)
- State two main uses of sodium hypochlorite(Solved)
State two main uses of sodium hypochlorite
Date posted: September 25, 2018. Answers (1)
- Describe how one can collect dry oxygen after preparation(Solved)
Describe how one can collect dry oxygen after preparation
Date posted: August 22, 2018. Answers (1)
- A student was provided with the following chemicals. Describe consecutively how to test presence of nitrates in sample solution (Solved)
A student was provided with the following chemicals
•4 cm^3 sample solutions in a test tube(KNO3)
•1M Sodium hydroxide
•Aluminium foil
•Source of heat
•Red and blue litmus paper
•Distilled water
Describe consecutively how to test presence of nitrates in sample solution
Date posted: August 22, 2018. Answers (1)
- Give two factors one should consider in siting carbonate manufacturing plant(Solved)
Give two factors one should consider in siting carbonate manufacturing plant
Date posted: August 22, 2018. Answers (1)
- The following are steps carried by a student during a chemistry practical to determine the concentration of an acid using...(Solved)
The following are steps carried by a student during a chemistry practical to determine the concentration of an acid using a known concentration of a base. Study the steps and answer the questions that follows(note:Steps are not consecutively)
(a) Rinse conical, pipette and burette using distilled water
(b)Assemble apparatus required set them
(c) Pour HCL to a burette
(d) Put a funnel on top of a burette
(e) Open burette tap to adjust volume of acid to a mark
(f) Add three drops of phenolphthalein indicator into conical flask.
(g) Titrate burette contents(acid) against conical contents(base) until the pink colour just disappear
(h) Suck 1M sodium hydroxide using pippete
and transfer to conical flask.
(I) Record the volume of acid used and repeat the procedure.
Questions
(I)Using alphabets (a-i) give the correct order of steps
(II) Why is it necessary to add an indicator to contents in conical flask and not the ones in burette?
(III) How can one determine end point?
(Iv) Write balance equation between acid and base
Date posted: August 20, 2018. Answers (1)
- (a) Define the following terms (I) Molar mass (II) A molar solution (III)Standard Solution (Iv)End point(Solved)
(a) Define the following terms(4mks)
(I) Molar mass
(II) A molar solution
(III)Standard Solution
(Iv)End point
Date posted: August 20, 2018. Answers (1)
- State two advantages of using natural polymers over synthetic ones(Solved)
State two advantages of using natural polymers over synthetic ones
Date posted: August 19, 2018. Answers (1)
- Dilute sulphuric (VI) acid reacts with aqueous sodium hydroxide to form a salt. Give the formula and name of the anion in the salt.(Solved)
Dilute sulphuric (VI) acid reacts with aqueous sodium hydroxide to form a salt. Give the formula and name of the anion in the salt.
Date posted: August 19, 2018. Answers (1)
- Calculate the number of chloride ions in a 250cm3 of 1M solution calcium chloride(Solved)
Calculate the number of chloride ions in a 250cm3 of 1M solution calcium chloride (Avogadro’s number is 6.0 × 1023)
Date posted: August 19, 2018. Answers (1)
- On complete combustion of a hydrocarbon gas X, 1.32g of carbon (IV) oxide and 0.54g of water. Calculate the empirical formula of X(Solved)
On complete combustion of a hydrocarbon gas X, 1.32g of carbon (IV) oxide and 0.54g of water. Calculate the empirical formula of X (C = 12.0, H = 1, O = 16.0)
Date posted: August 19, 2018. Answers (1)
- Study the following information and answer the question that follows(Solved)
Study the following information and answer the question that follows.
Heat of hydration of x2+ = -1480 kJ/mol
Heat of hydration y- = -364 kJ/mol
Lattice energy of XY2 = +2112 kJ/mol
Determine the heat evolved when 31.8g of XY2(s) is dissolved in water to give an infinitely dilute solution. (RAM of Z = 88, Y = 35.5)
Date posted: August 19, 2018. Answers (1)
- Distinguish between a strong acid and a concentrated acid(Solved)
Distinguish between a strong acid and a concentrated acid
Date posted: August 19, 2018. Answers (1)
- Give two reasons why during preparation of salt, it is advisable to heat the solution to concentration allowing it to cool in order to crystallize(Solved)
Give two reasons why during preparation of salt, it is advisable to heat the solution to concentration allowing it to cool in order to crystallize instead of heating to dryness.
Date posted: August 19, 2018. Answers (1)
- In an experiment it was found that 40.0cm3 of 0.2M sodium hydroxide solution just neutralized 0.2g of a dibasic acid Q..(Solved)
In an experiment it was found that 40.0cm3 of 0.2M sodium hydroxide solution just neutralized 0.2g of a dibasic acid Q. Calculate the relative molecular mass of acid Q.
Date posted: August 19, 2018. Answers (1)
- The nitrates of the following metals were heated strongly and observation made accordingly. The nitrate of metal P produced the metallic oxide, Nitrogen (IV) oxide and oxygen gas(Solved)
The nitrates of the following metals were heated strongly and observation made accordingly. The nitrate of metal P produced the metallic oxide, Nitrogen (IV) oxide and oxygen gas; and that of metal Q produced the metallic nitrite and oxygen gas. The nitrate of R produced metal R, Nitrogen (IV) oxide and oxygen gas. Arrange the metals in order of reactivity beginning with the most reactive
Date posted: August 19, 2018. Answers (1)
- A student was asked to prepare Lead (II) chloride salt using the following ingredients; Nitric (V) acid, lead (II) oxide and hydrochloric..(Solved)
A student was asked to prepare Lead (II) chloride salt using the following ingredients; Nitric (V) acid, lead (II) oxide and hydrochloric acid. Using ionic equations only explain how the salt can be prepared.
Date posted: August 19, 2018. Answers (1)
- Paper chromatography is a method of separating colours or dyes. What two properties should the components of a mixture have...(Solved)
Paper chromatography is a method of separating colours or dyes.
What two properties should the components of a mixture have that would make the separation possible
Date posted: August 19, 2018. Answers (1)
- Dilute nitric acid is added to excess green solid. Effervescence occurs and a blue solution is formed. When excess ammonia solution is added to a sample..(Solved)
Dilute nitric acid is added to excess green solid. Effervescence occurs and a blue solution is formed. When excess ammonia solution is added to a sample of the solution a deep blue solution is formed.
Identify the anion and cation in the green solid.
Date posted: August 18, 2018. Answers (1)