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They are stronger than natural fibres/OR are not easily affected by chemicals/lasts
longer /durable/ can be produced easily in a large scale therefore cheaper
Kavungya answered the question on June 22, 2019 at 04:20
- Calculate the amount of calcium carbonate that would remain if 15.0g of calcium
carbonate were reacted with 0.2 moles of hydrochloric acid.
The equation for the reaction...(Solved)
Calculate the amount of calcium carbonate that would remain if 15.0g of calcium
carbonate were reacted with 0.2 moles of hydrochloric acid.
The equation for the reaction is CaCO3 (g) + 2HCl CaCl2 (aq) + CO2 (g) + H2O (g)
(C = 12.0 = 1.60, Ca = 40.0)
Date posted: June 22, 2019. Answers (1)
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Date posted: June 12, 2019. Answers (1)
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Date posted: June 9, 2019. Answers (1)
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You are provided with the following reagents; dilute nitric acid, dilute sulphuric acid, and lead (II) oxide.
Describe clearly how you would prepare a sample of lead (II) sulphate.
Date posted: June 6, 2019. Answers (1)
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Date posted: June 6, 2019. Answers (1)
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Date posted: June 4, 2019. Answers (1)
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Date posted: May 24, 2019. Answers (1)
- The grid below shows part of the periodic table. Study it and answer the questions that follows.
a) Give the name of the elements represented by...(Solved)
The grid below shows part of the periodic table. Study it and answer the questions that follows.
a) Give the name of the elements represented by the shaded region.
b) Identify an element which form ion with +2 charge.
c) Which non-metal is most reactive ?
d) Element V is in the second period and group V of the periodic table. Place it on the above grid of the periodic table.
e) State and explain how the atomic radius of U and J compare.
f) Write a chemical equation for the reaction between the oxide of A and water.
g) Explain how the electrical conductivity of A and Y compare.
Date posted: May 24, 2019. Answers (1)
- Study the information given in the table below and answer the questions below.
Calculate the enthalpy change for the reaction.
CH4(g) + Cl2(g) ---> CH3Cl(g) +...(Solved)
Study the information given in the table below and answer the questions below.
Calculate the enthalpy change for the reaction.
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Date posted: May 24, 2019. Answers (1)
- Below is a simple representation of a soap molecule
(Solved)
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Using the structure above show how soap removes an oily smear from the fabric shown below.
Date posted: May 24, 2019. Answers (1)
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Date posted: May 24, 2019. Answers (1)
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Bottle of sodium carbonate, sodium chloride and sugar have lost their labels. A student prepares and tests an aqueous solution of a sample of each bottle. The results obtained are as shown below.
Complete the table by filling the correct label for each bottle.
Date posted: May 24, 2019. Answers (1)
- Study the scheme below and answer the questions that follow.
a) Draw the structure of polymer P.
b) Identify compound S.
c) Give the reagents and...(Solved)
Study the scheme below and answer the questions that follow.
a) Draw the structure of polymer P.
b) Identify compound S.
c) Give the reagents and conditions for step I and II
Step I:
Reagent
Condition
Step II:
Reagent
Condition
Date posted: May 24, 2019. Answers (1)
- An element Q has a relative atomic mass of 88. When a current of 0.5A was passed through the fused chloride of Q for 32
minutes...(Solved)
An element Q has a relative atomic mass of 88. When a current of 0.5A was passed through the fused chloride of Q for 32 minutes and 10 seconds, 0.44g of Q were deposited at cathode. Determine the charge on the ion of Q. (1 Faraday = 9650
Date posted: May 24, 2019. Answers (1)
- The electronic structures for elements represented by letters A, B, C and D are
A - 2.8.6 B - 2.8.2 C - 2.8.1 D - 2.8.8
a)...(Solved)
The electronic structures for elements represented by letters A, B, C and D are
A - 2.8.6 B - 2.8.2 C - 2.8.1 D - 2.8.8
a) Select the element which forms :
i) a double charged cation
ii) a soluble carbonate
b) Which element has the shortest atomic radius ?
Date posted: May 24, 2019. Answers (1)
- Some water samples A, B and C were tested with soap solution. The lathering produced was recorded as good or poor. The results are in...(Solved)
Some water samples A, B and C were tested with soap solution. The lathering produced was recorded as good or poor. The results are in the table below.
a) Identify the anions present in sample of water A.
b) Give an advantage of hard water.
c) State one structural difference between a soapy and soapless detergent.
Date posted: May 24, 2019. Answers (1)