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- 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)
(i) What is meant by ionization energy?
(ii) Element R has the lowest ionization energy. Explain
(iii) When a piece of element Q is placed on water it melts and a hissing sound is produced as it moves on the water surface. Explain these observations
(iv) Write the equation for the reaction between element Q and water
Date posted: October 15, 2019. Answers (1)
- Part of the periodic table is given below study it and answer the questions that follow.
The letters do not represent the actual elements(Solved)
Part of the periodic table is given below study it and answer the questions that follow.
The letters do not represent the actual elements
(i) What type of bond is formed when Y reacts with Z. Explain
(ii) Explain the difference in the atomic radii of element A and B
(iii) Explain the difference in the reactivity of Z and B
Date posted: October 15, 2019. Answers (1)
- The grid below represents part of the periodic table. The letters do not represent actual symbols of the elements. Study it and answer the questions...(Solved)
The grid below represents part of the periodic table. The letters do not represent actual symbols of the elements. Study it and answer the questions that follow:-
(a) What type of bond would you expect in the compound formed between H and F. Explain
(b) (i) Which of the elements J and M will have a greater atomic radius? Explain
(ii) Elements F and N are in the same group of periodic table. How do their atomic
radius compare? Explain
(c) An element W has atomic number 15. Indicate the position it would occupy in the table above
(d) What is the name given to elements X – Z?
(e) Why is J used in electric cables where Q is not
(f) P and J are termed as metalloids. What does the term metalloid mean?
(g) How would you expect the reactivity of H and M to compare? Explain
Date posted: October 15, 2019. Answers (1)
- Sodium metal tarnishes when exposed to the air where a white powder is formed on its
surface. A small piece of this sodium metal was dropped...(Solved)
Sodium metal tarnishes when exposed to the air where a white powder is formed on its
surface. A small piece of this sodium metal was dropped into 25g of ethanol and 1200cm3
of hydrogen gas was evolved at r.t.p. The unreacted ethanol was evaporated and a white
solid remained. (Na=23, molar gas volume at r.t.p = 24dm3, C=12, O =16, H=1)
(a) Write a chemical equation for the reaction between ethanol and sodium metal
(b) Determine the mass of sodium that reacted with ethanol
(c) What mass of ethanol evaporated?
(d) The ethanol was evaporated at 80oC, while the white solid remained unaffected at this
temperature. What is the difference in structure of ethanol and the white solid?
(II) (a) Name an inorganic liquid which liberates hydrogen gas with sodium metal
(b) What two differences would you observe if similar pieces of sodium were dropped
separately into small beakers containing equal amount of ethanol and the liquid
named in (II)(a) above respectively
Date posted: October 15, 2019. Answers (1)
- Explain the following observations:-
(i) NaCl allows electric current to pass through them in molten state
(ii) Graphite is a non-metal yet it is a conductor of...(Solved)
Explain the following observations:-
(i) NaCl allows electric current to pass through them in molten state
(ii) Graphite is a non-metal yet it is a conductor of electricity
Date posted: October 15, 2019. Answers (1)
- Explain how electrical conductivity can be used to distinguish between magnesium oxide and silicon (IV) oxide(Solved)
Explain how electrical conductivity can be used to distinguish between magnesium oxide and silicon (IV) oxide
Date posted: October 15, 2019. Answers (1)
- Explain why luminous flame is capable of giving out light and soot(Solved)
Explain why luminous flame is capable of giving out light and soot
Date posted: October 15, 2019. Answers (1)
- Water has a boiling point of 100oC while hydrogen chloride has a boiling point of -115oC. Explain(Solved)
Water has a boiling point of 100oC while hydrogen chloride has a boiling point of -115oC. Explain
Date posted: October 15, 2019. Answers (1)
- Between aluminium and copper which one is a better conductor? Explain(Solved)
Between aluminium and copper which one is a better conductor? Explain
Date posted: October 15, 2019. Answers (1)
- Using dots and crosses to represent electrons, draw the structures of the following:
(a) Phosphorous chloride (PCl3)
(b) Hydroxonium ion (H3O+)(Solved)
Using dots and crosses to represent electrons, draw the structures of the following:
(a) Phosphorous chloride (PCl3)
(b) Hydroxonium ion (H3O+)
Date posted: October 15, 2019. Answers (1)
- Draw a diagram to show bonding in an ammonium ion. (N = 7, H = 1)(Solved)
Draw a diagram to show bonding in an ammonium ion. (N = 7, H = 1)
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 elements P, Q and R belong?
(b) Explain why P has the highest ionization energy
(c) Write a balanced chemical equation for the reaction between element Q and water
Date posted: October 15, 2019. Answers (1)
- The information in the table below relates to elements in the same group of the periodic table.
Study it and answer the question that follows.(Solved)
The information in the table below relates to elements in the same group of the periodic table.
Study it and answer the question that follows.
Which element has the highest ionization energy? Explain
Date posted: October 15, 2019. Answers (1)
- 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)