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- Arch welding
- Bulbs to prevent oxidation of the filament
sharon kalunda answered the question on May 21, 2019 at 07:12
- Solutions can be classified as acids bases or neutral. The table below shows solutions and their pH values.(Solved)
Solutions can be classified as acids bases or neutral. The table below shows solutions and their pH values.
(i) Select any pair that would react to form a solution of pH 7
(ii) Identify two solutions that would react with Aluminium hydroxide. Explain.
Date posted: May 21, 2019. Answers (1)
- Study the following equilibrium reaction. Suggest two ways of increasing the yield of A2B.(Solved)
Study the following equilibrium reaction
.
Suggest two ways of increasing the yield of A2B.
Date posted: May 21, 2019. Answers (1)
- D grams of potassium hydroxide were dissolved in distilled water to make 100cm3 of
solution. 50cm3 of the solution required 50cm3 of 2.0M nitric acid for...(Solved)
D grams of potassium hydroxide were dissolved in distilled water to make 100cm3 of
solution. 50cm3 of the solution required 50cm3 of 2.0M nitric acid for complete neutralization.Calculate the mass D of potassium hydroxide.
(relative formula of KOH=56)
Date posted: May 21, 2019. Answers (1)
- Element A has atomic mass 23 and element B atomic mass 7 and also have 12 neutrons and 4 neutrons respectively.(Solved)
Element A has atomic mass 23 and element B atomic mass 7 and also have 12 neutrons and 4 neutrons respectively.
a) Write the electron arrangement of A and B
b) Which element has higher ionization energy? Explain
Date posted: May 21, 2019. Answers (1)
- When hydrogen chloride gas is dissolved in water the solution formed turns blue litmus paper red but there is no effect on blue litmus paper...(Solved)
When hydrogen chloride gas is dissolved in water the solution formed turns blue litmus paper red but there is no effect on blue litmus paper when the gas is dissolved in carbon tetra chloride.Explain
Date posted: May 21, 2019. Answers (1)
- When lead (II) carbonate reacts with dilute hydrochloric acid, very little carbon (iv) oxide is produced.Explain(Solved)
When lead (II) carbonate reacts with dilute hydrochloric acid, very little carbon (iv) oxide is produced.Explain
Date posted: May 21, 2019. Answers (1)
- Using reagents provided only, explain by means of balanced chemical equations how you
could prepare a salt of Zinc carbonate solid.
Zinc powder
Nitric (V) acid...(Solved)
Using reagents provided only, explain by means of balanced chemical equations how you
could prepare a salt of Zinc carbonate solid.
Zinc powder
Nitric (V) acid (dilute)
Water
Solid sodium carbonate
Date posted: May 21, 2019. Answers (1)
- Consider the Zinc nuclide below
Determine the number of protons and neutrons in the nuclide.(Solved)
Consider the Zinc nuclide below
Determine the number of protons and neutrons in the nuclide.
Date posted: May 21, 2019. Answers (1)
- Given the equation for reaction below Calculate
(i) Volume of chlorine at (r.t.p) required to react with 3g of Aluminium (Molar gas volume at r.t.p =...(Solved)
Given the equation for reaction below
Calculate
(i) Volume of chlorine at (r.t.p) required to react with 3g of Aluminium (Molar gas volume at r.t.p = 24litres, Al = 27, Cl = 35.5).
(ii) Mass of Aluminium chloride formed.
Date posted: May 21, 2019. Answers (1)
- 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)