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- Calculate the solubility of sugar in water at 40oC from the following information.
Mass of evaporating dish = 23.0g
Mass of evaporating dish + sample of saturated...(Solved)
Calculate the solubility of sugar in water at 40oC from the following information.
Mass of evaporating dish = 23.0g
Mass of evaporating dish + sample of saturated solution = 192.0g
Mass of evaporation dish + solid after evaporating of solution + 142.0g
Date posted: May 21, 2019. Answers (1)
- Write the formula of the complex ion formed when excess ammonia gas is passed through a solution containing Zn2+ ions.(Solved)
Write the formula of the complex ion formed when excess ammonia gas is passed through a solution containing Zn2+ ions.
Date posted: May 21, 2019. Answers (1)
- The apparatus below was a set up to show the catalytic oxidation of ammonia. Study the diagram and answer the questions that follow.
(i) Write an...(Solved)
The apparatus below was a set up to show the catalytic oxidation of ammonia. Study the diagram and answer the questions that follow.
(i) Write an equation for the reaction that takes place in the gas jar.
(ii) Why is it necessary to have a hot nichrome wire in the gas jar.
Date posted: May 21, 2019. Answers (1)
- Use the chart below to answer the questions that follow.
Identify:
Gas P
Solid R
Solid T .
Liquid S(Solved)
Use the chart below to answer the questions that follow.
Identify:
Gas P
Solid R
Solid T .
Liquid S
Date posted: May 21, 2019. Answers (1)
- Name the following compounds using the IUPAC system.(Solved)
Name the following compounds using the IUPAC system.
Date posted: May 21, 2019. Answers (1)
- Give the structural formula of 3, 3-dimethly pent-l-yne(Solved)
Give the structural formula of 3, 3-dimethly pent-l-yne
Date posted: May 21, 2019. Answers (1)
- One use of electrolysis is electroplating as shown below.(Solved)
One use of electrolysis is electroplating as shown below.
(i) To what terminal of the power source is the key connected
(ii) Name the most suitable material for electrode K
(iii) Write the
(iv) If 3A power source was used for 5 hours, calculate the increase in mass of the Key.
( Ag = 108, 1 Fa=96500C)
Date posted: May 21, 2019. Answers (1)
- State the particles responsible for conductivity of an electric current in
(i) Solution
(ii) A metal(Solved)
State the particles responsible for conductivity of an electric current in
(i) Solution
(ii) A metal
Date posted: May 21, 2019. Answers (1)
- The scheme below shows a series of reactions starting with Propanol. Study it and answer the questions that follow.
(a) (i) Name the type of reaction...(Solved)
The scheme below shows a series of reactions starting with Propanol. Study it and answer the questions that follow.
(a) (i) Name the type of reaction in steps I and II
(b) Write the equation for the reaction that takes place in Step III
(c) Name substances labeled A,C,D and E
(d) Draw the structural formula of product C .
(e) Name the process in Step (IV).
(f) Name compound B and state the type of reaction involved in its formation
Name of compound B……………………………………………………………
Type of reaction………………………………………………………………….
(g) If the relative molecular mass of B is 35,700 determine the value of n
Date posted: May 21, 2019. Answers (1)
- Study the diagram below and use it to answer the questions that follow.
(i) Name liquids A and B
(ii) Suggest a suitable reagent that can be...(Solved)
Study the diagram below and use it to answer the questions that follow.
(i) Name liquids A and B
(ii) Suggest a suitable reagent that can be used as solid D
(iii) State the role of Solid D
(iv) Write a balanced chemical equation for the reaction in the conical flask
(v) Explain why solid C collects further away from the heated aluminium metals.
Date posted: May 20, 2019. Answers (1)
- Study the information given in the table below and answer the questions that follow.
(i) Explain why the melting point and boiling points of MgCl2 are...(Solved)
Study the information given in the table below and answer the questions that follow.
(i) Explain why the melting point and boiling points of MgCl2 are very high yet melting
point and boiling point of PCl3 are very low.
(ii) Explain by use of a chemical equation why a solution when AlCl3 reacts with water
has a pH of 3
Date posted: May 20, 2019. Answers (1)
- The table below shows some properties and electronic arrangement of ions of elements represented by letters P to X. Study the information and answer the...(Solved)
The table below shows some properties and electronic arrangement of ions of elements represented by letters P to X. Study the information and answer the questions that follow. The letters are not the actual symbols of elements.
(i) Give the atomic numbers of elements T and V
(ii) What is the name given to the family of elements to which R,V and W belong.
(iii) Explain why:
I .The atomic radius of S is smaller than that of V
II. the atomic radius of R is larger than its ionic radius
(iv) Using dots (•) and crosses (x) to represent outermost electrons, show the bonding in
the compound formed between U and X
(v) Describe how a mixture of V chlorine s Lead(II) chloride can be separated
Date posted: May 20, 2019. Answers (1)
- Determine the relative atomic mass of the argon whose isotopic mixture is:(Solved)
Determine the relative atomic mass of the argon whose isotopic mixture is:
Date posted: May 20, 2019. Answers (1)
- 40cm3of carbon(II) oxide and 40 cm3 of oxygen were sparked in a closed vessel.
(i) Write a chemical equation for the reaction that occurs.
(ii) Determine...(Solved)
40cm3of carbon(II) oxide and 40 cm3 of oxygen were sparked in a closed vessel.
(i) Write a chemical equation for the reaction that occurs.
(ii) Determine the composition of the residual gases.
Date posted: May 20, 2019. Answers (1)
- The main ore of copper is low grade. Describe how the main ore can be concentrated.(Solved)
The main ore of copper is low grade. Describe how the main ore can be concentrated.
Date posted: May 20, 2019. Answers (1)
- Name and give the chemical formula of the chief ore of copper.(Solved)
Name and give the chemical formula of the chief ore of copper.
Date posted: May 20, 2019. Answers (1)
- The graphs below represents the temperature-time curves for solids M and N(Solved)
The graphs below represents the temperature-time curves for solids M and N
(a) What is the name given to the curves above?.
(b) Which of the two solids is an impure substance? Explain.
Date posted: May 20, 2019. Answers (1)
- Given that:
State and explain whether silver nitrate can be stored in a container made of Q(Solved)
Given that:
State and explain whether silver nitrate can be stored in a container made of Q
Date posted: May 20, 2019. Answers (1)
- Study the structure below and answer the questions that follow.
(a) Name the polymer represented by the structure.
(b) Draw the structure of the monomer and name...(Solved)
Study the structure below and answer the questions that follow.
(a) Name the polymer represented by the structure.
(b) Draw the structure of the monomer and name it.
Structure
Date posted: May 20, 2019. Answers (1)
- State one large scale use of sulphuric (VI) acid(Solved)
State one large scale use of sulphuric (VI) acid
Date posted: May 20, 2019. Answers (1)