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Covalent bonds exist between two iodine atoms in an iodine molecule while Van der waals forces exists between two or more molecules of iodine. Covalent bonds are strong than Van der walls forces
johnmulu answered the question on February 2, 2017 at 09:16
- Oxygen and sulphur belong to group (VI) of the periodic table. Explain why there is a big difference in their melting points (melting points of oxygen is -216oC) while that of sulphur is 44oC(Solved)
Oxygen and sulphur belong to group (VI) of the periodic table. Explain why there is a big difference in their melting points (melting points of oxygen is -216oC) while that of sulphur is 44oC
Date posted: February 2, 2017. Answers (1)
- The melting point of phosphorus trichloride is - 91oC while that of magnesium chloride is 715oC.(Solved)
The melting point of phosphorus trichloride is - 91oC while that of magnesium chloride is 715oC. In terms of structure and bonding, explain the difference in their melting points
Date posted: February 2, 2017. Answers (1)
- Compound Q is a solid with a giant ionic structure. In what forms would be compound conduct an electric current?(Solved)
Compound Q is a solid with a giant ionic structure. In what forms would be compound conduct an electric current?
Date posted: February 2, 2017. Answers (1)
- What type of bond is formed when lithium and fluorine react?(Solved)
What type of bond is formed when lithium and fluorine react? Explain
(Atomic numbers: Li = 3 F = 9)
Date posted: February 2, 2017. Answers (1)
- Diamond and graphite are allotropes of carbon. In terms of structure and bonding explain the following(Solved)
Diamond and graphite are allotropes of carbon. In terms of structure and bonding explain the following:
i) Diamond is used in drilling through hard rocks
ii) Graphite is used as a lubricant
Date posted: February 2, 2017. Answers (1)
- State two uses of diamond(Solved)
State two uses of diamond.
Date posted: February 2, 2017. Answers (1)
- Give the name of the product formed when magnesium reacts with phosphorus(Solved)
Give the name of the product formed when magnesium reacts with phosphorus.
Date posted: February 2, 2017. Answers (1)
- Explain why the reactivity of group (VII) elements decreases down the group(Solved)
Explain why the reactivity of group (VII) elements decreases down the group.
Date posted: February 2, 2017. Answers (1)
- An atom of hydrogen can form two ions. Write two equations to show how a neutral atom of hydrogen can form two ions(Solved)
An atom of hydrogen can form two ions. Write two equations to show how a neutral atom of hydrogen can form two ions. In each case show the sign of energy change involved.
Date posted: February 2, 2017. Answers (1)
- Name one property of neon that makes it possible to be used in electric lamps(Solved)
Name one property of neon that makes it possible to be used in electric lamps.
Date posted: February 2, 2017. Answers (1)
- Explain why hydrogen forms compounds in which its oxidation state is either + 1 or -1 (Atomic number of hydrogen is 1)(Solved)
Explain why hydrogen forms compounds in which its oxidation state is either + 1 or -1 (Atomic number of hydrogen is 1)
Date posted: February 2, 2017. Answers (1)
- Give two reasons why helium is used in weather balloons(Solved)
Give two reasons why helium is used in weather balloons.
Date posted: February 2, 2017. Answers (1)
- Write the formula of sulphide of an element C, whose atomic number is 5. C is not the actual symbol of the element(Solved)
Write the formula of sulphide of an element C, whose atomic number is 5. C is not the actual symbol of the element.
Date posted: February 2, 2017. Answers (1)
- An element Y has the electronic configuration 2.8.5(Solved)
An element Y has the electronic configuration 2.8.5
a) which period of the periodic table does the element belong
b) Write a formula of the most stable anion formed when element Y ionises
c) Explain the difference between the atomic radius of element Y and its ionic radius
Date posted: February 2, 2017. Answers (1)
- Distinguish between ionisation energy and electron affinity of an element(Solved)
Distinguish between ionisation energy and electron affinity of an element.
Date posted: February 2, 2017. Answers (1)
- What name is given to an element which appears in group (II) of the periodic table?(Solved)
What name is given to an element which appears in group (II) of the periodic table?
Date posted: February 2, 2017. Answers (1)
- The atomic numbers of phosphorus, sulphur and potassium are 15, 16 and 19 respectively. The formulae of their ions are P3-, S2- and K+. These ions have the same number of electrons(Solved)
The atomic numbers of phosphorus, sulphur and potassium are 15, 16 and 19 respectively. The formulae of their ions are P3-, S2- and K+. These ions have the same number of electrons
i) Write the electron arrangement of the ions
ii) Arrange the ions in the increasing ionic radius starting with the smallest. Give a reason for the order
Date posted: February 2, 2017. Answers (1)
- What is meant by the terms (i) Element (ii) Atomic number (Solved)
What is meant by the terms
i) Element
ii) Atomic number
Date posted: February 2, 2017. Answers (1)
- What are isotopes?(Solved)
What are isotopes?
Date posted: February 2, 2017. Answers (1)
- Why is calcium more reactive than beryllium?(Solved)
Why is calcium more reactive than beryllium?
Date posted: February 2, 2017. Answers (1)