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R – has the smallest atomic size hence its outermost electrons are more strongly held to the nucleus resulting in high value of ionization energy
maurice.mutuku answered the question on October 15, 2019 at 07:19
- The table below shows elements A, B, C, E, F, and G. Elements in group X have a valency of 2 while elements in group...(Solved)
The table below shows elements A, B, C, E, F, and G. Elements in group X have a valency of 2 while elements in group Y have a valency of 1. Use the table to answer the questions that follow:-
(i) Atomic radius increases from A to C and from E to G. Explain
(ii) Explain the difference in the atomic and ionic radii of group X elements
(iii) Elements C and G belong to the same period. Explain why the atomic radius of C is
greater than that of G
(iv) Give the formula of the compound formed when B and F react
(v) What type of bonding is formed in the compound above? Explain
(vi) Starting with the least reactive, arrange the elements in group Y in the order of reactivity.
Explain:
Date posted: October 15, 2019. Answers (1)
- Study the information in the table below and answer the questions that follow. The letters do not represent the actual symbols of the elements.(Solved)
Study the information in the table below and answer the questions that follow. The letters do not represent the actual symbols of the elements.
(a) What is the general name given to the group in which the elements X, Y and Z belong?
(b) Select two elements which are coloured gases
(c) Explain why Z has the highest boiling point
(d) Write an equation for the reaction of element Z with iron metal
(e) Element Y was dissolved in water and a piece of blue litmus paper was put into the resulting solution. State and explain the observation that was made on the litmus paper
Date posted: October 15, 2019. Answers (1)
- State the reason for using Argon in electric light bulbs(Solved)
State the reason for using Argon in electric light bulbs
Date posted: October 15, 2019. Answers (1)
- Study the information in the table below and answer the questions that follow:(Solved)
Study the information in the table below and answer the questions that follow:
(a) Would these form part of a metallic or a non-metallic group? Explain
(b) Suggest an element in the table above likely to be the most reactive. Explain
Date posted: October 15, 2019. Answers (1)
- Study the information given below and answer the questions that follow:(Solved)
Study the information given below and answer the questions that follow:
(i) Write the formula of the compound formed when J combined with G
(ii) Explain why the melting point of the oxide of E is higher than that of the oxide of G
Date posted: October 15, 2019. Answers (1)
- Ethanol is a liquid at room temperature but does not conduct electricity. Explain.(Solved)
Ethanol is a liquid at room temperature but does not conduct electricity. Explain.
Date posted: October 15, 2019. Answers (1)
- Study the information in the table below and answer the questions that follow:(Solved)
Study the information in the table below and answer the questions that follow:
a) Write the electron arrangement of element P.
b) Give the group and period to which elements Q and R respectively.
Date posted: October 15, 2019. Answers (1)
- Compare with a reason the atomic radius of Sodium to that of Aluminum.(Solved)
Compare with a reason the atomic radius of Sodium to that of Aluminum.
Date posted: October 15, 2019. Answers (1)
- Identify the particles that facilitate the electric conductivity of the following substances
(i) Sodium metal
(ii) Sodium Chloride solution
(iii) Molten Lead Bromide(Solved)
Identify the particles that facilitate the electric conductivity of the following substances
(i) Sodium metal
(ii) Sodium Chloride solution
(iii) Molten Lead Bromide
Date posted: October 15, 2019. Answers (1)
- An element W has an atomic number 13.
a) Write the electronic configuration of the most stable ion of W
b) Write the formula of the oxide...(Solved)
An element W has an atomic number 13.
a) Write the electronic configuration of the most stable ion of W
b) Write the formula of the oxide of the element W
Date posted: October 15, 2019. Answers (1)
- The grid below is part of the periodic table. The elements are not represented by their actual symbols. Use the information to answer the questions...(Solved)
The grid below is part of the periodic table. The elements are not represented by their actual symbols. Use the information to answer the questions that follow.
a) (i) Which is the most reactive
(I) Non — metal?
Explain
(II) Metal?
Explain
(ii) Name the family to which elements T and Q belongs.
(iii) Write the formula of the compound formed when W reacts with S.
(iv) Name the type of bond and structure formed when elements R and K react.
(v) Explain why element N doesn’t form compounds with other elements.
(vi) Compare the atomic radii of T and Q. Explain.
Date posted: October 15, 2019. Answers (1)
- The grid below represents part of the periodic table. Study it and answer the questions that follow:(Solved)
The grid below represents part of the periodic table. Study it and answer the questions that follow:
(a) (i) Identify the element that gains electrons most readily
(ii) Which of the metal is most reactive? Explain
(iii) What name is given to the family of elements to which elements X and T belong?
(iv) Explain why:-
(I) Ionic radius of Q is larger than that of M
(II) Atomic radius of Q is greater than that of S
(v) Which of the element in the table does not have the ability to form an ionic or covalent
bond? Explain
(vi) Give the formula of the compound formed between R and Z
Date posted: October 15, 2019. Answers (1)
- The grid below represents part of the periodic table. The letters do not represent the actual symbols of the elements. Study it and answer the...(Solved)
The grid below represents part of the periodic table. The letters do not represent the actual symbols of the elements. Study it and answer the questions that follow:
(a) Explain why element L appears in two different groups in the grid above
(b) State the name of the chemical family to which P and Q belong
(c) Write the formula of the compound formed between P and V
(d) Compare the melting points of Q and S. Explain
(e) Identify an element whose oxide dissolves in both acids and alkalis
(f) Write the equation for the burning of T in excess air
(g) Using dots (•) and cross (x) to represent electrons, draw a diagram to illustrate bonding in the sulphide of Q
(h) State one use of element X
Date posted: October 15, 2019. Answers (1)
- Study the equation below:(Solved)
Study the equation below:
Mg(s) + 2H2O(l)------->Mg(OH)2(aq) + H2(g)
Which species has undergone oxidation .Explain
Date posted: October 15, 2019. Answers (1)
- Work out the oxidation number of phosphorous in the following compound H3PO3(Solved)
Work out the oxidation number of phosphorous in the following compound H3PO3
Date posted: October 15, 2019. Answers (1)
- Study the table below and answer the questions that follow.(Solved)
Study the table below and answer the questions that follow.
(i) Complete the table above
(ii) From the table, choose the most reactive metal. Explain
(iii) Which element is the most electronegative. Explain
(iv) Using dots (.) and crosses (x) to represent electrons, show the bonding in the chloride of Q
(v) Explain the solubility of element T in water
(b) (i) Why is aluminium used to make utensils yet it is a reactive metal?
Date posted: October 15, 2019. Answers (1)
- The grid below shows a part of the periodic table. The letters do not represent the actual symbols.(Solved)
The grid below shows a part of the periodic table. The letters do not represent the actual symbols.
Use it to answer the questions that follow:-
(a) How do the atomic radius of element X and Y compare
(b) (i) Using crosses (X) to represent electrons, draw the atomic structure of element Q
(ii) State the period and the group to which element Q belong
(c) (i) The ionic configuration of element G is 2.8 G forms an ion of the type G-1.
Indicate on the grid, the position of element G.
(ii) To which chemical family does element G belong?
(iii) State one use of element U
(iv) What is the nature of the compound formed between K and U
Date posted: October 15, 2019. Answers (1)
- The following flow chart shows the industrial manufacture of Nitric (V) acid.(Solved)
The following flow chart shows the industrial manufacture of Nitric (V) acid.
a) Identify substance B, C, E and F.
b) Describe what happens in the catalytic chamber.
c) State what takes place in chamber D.
d) 60 – 65% nitric (V) acid is produced in the absorption chamber. Describe how the acid can be
concentrated.
Date posted: October 14, 2019. Answers (1)
- The grid below is part of the periodic table. Use it to answer the questions that follow:(Solved)
The grid below is part of the periodic table. Use it to answer the questions that follow:
a) Write down the formula of the compound formed between C and A.
b) Which element has the same electron arrangement as the stable ion of:
(i) F (ii) A
c) Element Q has atomic number 15. Indicate its position on the grid.
d) Explain how the atomic radii of the following compare:
(i) C and F
(ii) C and D
e) Write the type of bond present in a compound formed between D and A.
f) Compound C and G were completely burned in oxygen.
(i) Write down equations to show the combustion of each of the elements.
(ii) State whether each of the oxides (i) above is basic or acidic.
Date posted: October 14, 2019. Answers (1)
- Define the term melting point of a substance(Solved)
Define the term melting point of a substance
Date posted: October 14, 2019. Answers (1)