i.Avoid naked flames/use sand bath or water bath.
ii.Slant the test tube/avoid spitting.
sharon kalunda answered the question on August 5, 2019 at 13:18
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Date posted: August 5, 2019. Answers (1)
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a) Name any two impurities removed by the purifier.
b) The catalyst used in the process is finely divided iron. Why iron is finely divided?
c) In the Haber process the conversion of nitrogen and hydrogen into ammonia is only 10%.
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Date posted: August 5, 2019. Answers (1)
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(a) Select two elements with oxidation states of -3.
(b) Which elements represent the most powerful reducing agent? Explain.
(c) Which element has the highest ionization energy?
(d) Select two elements which when reacted form a compound that conducts electricity both in molten and aqueous state.
(e) Select any two elements which when reacted form a compound that dissolves in water to form an acidic solution.
(f) Using dots (●) and crosses (X) to represent electrons; draw diagrams to show bonding between B and J.
(g) Explain why for some elements the atomic mass is not twice the atomic number.
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Write the formulae of the salts that would be...(Solved)
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sample reacted completely with...(Solved)
In an experiment to determine the percentage purity of the sample of
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sample reacted completely with 40.0cm3 of 0.5 M sulphuric acid.
I calculate the number of moles of sodium carbonate that
reacted.
II Determine the percentage of sodium carbonate in the
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Date posted: June 24, 2019. Answers (1)
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Calculate the volume of chlorine gas used (Molar gas volume is 24dm3, al = 27).(Solved)
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Calculate the volume of chlorine gas used (Molar gas volume is 24dm3, al = 27).
Date posted: June 24, 2019. Answers (1)
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a) Write equation for the formation of aluminium metal
b) Calculate the quantity of electricity in faradays...(Solved)
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obtained.
a) Write equation for the formation of aluminium metal
b) Calculate the quantity of electricity in faradays used (Al=27)
Date posted: June 24, 2019. Answers (1)
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Calculate the;
(i) Number of moles of methane in...(Solved)
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contains 5.0 kg of the gas.
Calculate the;
(i) Number of moles of methane in the cylinder. (Molar mass of methane=16)
(ii) Total volume of carbon (IV) oxide produced by the combustion of methane in the
cylinder (Molar gas Volume=24.0 dm-3+ at room temperature and pressure).
Date posted: June 24, 2019. Answers (1)
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solution containing 0.50 g of the anti-acid was neutralized by 23.0 cm3...(Solved)
In an experiment to determine the percentage of magnesium hydroxide in an anti-acid, a
solution containing 0.50 g of the anti-acid was neutralized by 23.0 cm3 of 0.010m
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a) Mass of magnesium hydroxide in the anti-acid;
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Date posted: June 24, 2019. Answers (1)
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product formed was 3.47 g
Calculate the:
(i) Maximum mass of...(Solved)
When 1.08g of aluminum foil were heated in a stream of chlorine gas, the mass of the
product formed was 3.47 g
Calculate the:
(i) Maximum mass of the product formed if chlorine was in excess;
(Al= 27; Cl = 35.5)
(ii) Percentage yield of the product formed
Date posted: June 24, 2019. Answers (1)