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a) Ionization energy is the minimum amount of energy required to remove an electron from the last energy level of an isolated neutral atom form a positively charged ion in gaseous state
b) The ionization energy decreases from K to T; this is because of the addition of an extra energy level from K to T which decreases the nuclear attraction hence easy to remove an electron from the outermost energy level
Group I; they all have one electron in their outermost energy level;
c) Both K and T have giant metallic structures. K has smaller atomic/ionic size with strong metallic bonds that require higher amount of energy to break hence high melting and boiling point compared to T.
marto answered the question on October 1, 2019 at 10:51
- The diagram below shows the effect of sunlight on chlorine water(Solved)
The diagram below shows the effect of sunlight on chlorine water.
a) Identify gas W
b) Write an equation to show the formation of gas W
c) Which compound is left in the beaker after complete formation of gas W?
Date posted: October 1, 2019. Answers (1)
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Study the flow chart below and answer the questions that follow.
a) Identify gas X
b) Write an equation for the reaction between ammonia and gas X
c) Write an equation to show the formation of G and J
Date posted: October 1, 2019. Answers (1)
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Form two students from Anestar Premier High School reacted three elements as shown in the table below.
Which element (s) is likely to be:
i) Non-metal (s)
ii) Metal (s)
iii) Insoluble in water
Date posted: October 1, 2019. Answers (1)
- If 25.0cm3 of 0.1 M H2SO4 solution neutralized a solution containing 1.06g of sodium carbonate in 250cm3 of solution, calculate the molarity and volume of...(Solved)
If 25.0cm3 of 0.1 M H2SO4 solution neutralized a solution containing 1.06g of sodium carbonate in 250cm3 of solution, calculate the molarity and volume of the sodium carbonate solution used.
Date posted: October 1, 2019. Answers (1)
- What volume of oxygen will be required for complete combustion of 100cm3 of carbon (II) oxide. What is the volume of the product formed (All...(Solved)
What volume of oxygen will be required for complete combustion of 100cm3 of carbon (II) oxide. What is the volume of the product formed (All volumes at same temperature and pressure
Date posted: October 1, 2019. Answers (1)
- Study the information in the table and answer questions that follow:(Solved)
Study the information in the table and answer questions that follow:
(a) Determine the number of neutrons of R1
(b) Calculate the relative atomic mass of element R.
Date posted: October 1, 2019. Answers (1)
- A compound of carbon, hydrogen and oxygen contains 71.12g by mass of oxygen, 2.2g hydrogen and the rest is carbon. It has relative molecular mass...(Solved)
A compound of carbon, hydrogen and oxygen contains 71.12g by mass of oxygen, 2.2g hydrogen and the rest is carbon. It has relative molecular mass of 90.
a) Determine the empirical formula of the compound
b) Determine the molecular formula of the compound
Date posted: October 1, 2019. Answers (1)
- Study the flow chart below and answer the questions that follow.(Solved)
Study the flow chart below and answer the questions that follow.
a) Identify the metal oxide.
b) Write an ionic equation leading to the formation of the white precipitate X.
c) Give the formula of the ions responsible for the colourless solution Y.
Date posted: October 1, 2019. Answers (1)
- The diagram below shows Chromatograms for five different dyes.(Solved)
The diagram below shows Chromatograms for five different dyes.
a) Name one condition required to separate the chromatograms present in a dye.
b) What is meant by the solvent front? .
c) Which chromatograms are present in dye E.
d) Name two industrial applications of chromatography
Date posted: October 1, 2019. Answers (1)
- The diagrams below show some physical methods of separating mixtures.(Solved)
The diagrams below show some physical methods of separating mixtures.
Name the methods of separation labeled W, X and Y
Date posted: October 1, 2019. Answers (1)
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Study the figure below and use it to answer the following questions.
a) Name the parts labeled X and Y.
b) Identify the flame.
c) Which part of the flame is the hottest?
Date posted: October 1, 2019. Answers (1)
- Candle wax is an example of a hydrocarbon.
a) What is a hydrocarbon
b)Name the two products formed when hydrocarbons burn in oxygen.(Solved)
Candle wax is an example of a hydrocarbon.
a) What is a hydrocarbon
b)Name the two products formed when hydrocarbons burn in oxygen.
Date posted: October 1, 2019. Answers (1)
- The set-up below was used to prepare a sample of oxygen gas. Study it and answer the questions that follow.(Solved)
The set-up below was used to prepare a sample of oxygen gas. Study it and answer the questions that follow.
a) Write a word equation for the reaction that produces oxygen above.
b) State two physical properties of oxygen gas.
c) State two uses of oxygen.
Date posted: October 1, 2019. Answers (1)
- State whether solutions with the following pH values are acidic, basic or neutral.
pH 3 –
pH 11 –
pH 14 –
pH 7 –(Solved)
State whether solutions with the following pH values are acidic, basic or neutral.
pH 3 –
pH 11 –
pH 14 –
pH 7 –
Date posted: October 1, 2019. Answers (1)
- Study the diagram below for the reaction between sodium carbonate and hydrochloric acid and answer the questions that follow(Solved)
Study the diagram below for the reaction between sodium carbonate and hydrochloric acid and answer the questions that follow.
a) Explain what was observed in:
i) Test tube A.
ii) Test tube B.
b) Write a word equation for the reaction which took place in test tube.
Date posted: October 1, 2019. Answers (1)
- Write word equations for the following reactions.(Solved)
Write word equations for the following reactions.
i) Zinc and hydrochloric acid.
ii) Potassium hydroxide and sulphuric (VI) acid.
iii) Magnesium carbonate and nitric (V) acid.
Date posted: October 1, 2019. Answers (1)
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Complete the following
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ii) Acid + Base →
iii) Acid + Carbonate →
Date posted: October 1, 2019. Answers (1)
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i) Atom.
ii) Compound.
iii) Element(Solved)
Define:
i) Atom.
ii) Compound.
iii) Element
Date posted: October 1, 2019. Answers (1)
- Write the names of the elements represented by symbols.(Solved)
Write the names of the elements represented by symbols.
i) K –
ii) Cl –
iii) Fe –
iv) Mg –
v) C –
vi) Be-
Date posted: October 1, 2019. Answers (1)
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Distinguish between temporary physical and permanent chemical changes.
Date posted: October 1, 2019. Answers (1)