Get premium membership and access questions with answers, video lessons as well as revision papers.
Across the period there is gradual increase in number of protons in the nucleus.
This increases the force of attraction between the nucleus and the electrons
johnmulu answered the question on February 2, 2017 at 12:42
- Yellow phosphorous reacts with chlorine gas to form a yellow liquid. The liquid fumes when exposed to air. Explain these observations (Solved)
Yellow phosphorous reacts with chlorine gas to form a yellow liquid. The liquid fumes when exposed to air. Explain these observations.
Date posted: February 2, 2017. Answers (1)
- Give a reason why phosphorus is stored under water(Solved)
Explain why Phosphorous is stored under water
Date posted: February 2, 2017. Answers (1)
- Explain why anhydrous aluminium chloride is fairly soluble in organic solvent while anhydrous magnesium chloride is insoluble(Solved)
Explain why anhydrous aluminium chloride is fairly soluble in organic solvent while anhydrous magnesium chloride is insoluble.
Date posted: February 2, 2017. Answers (1)
- A crystal of iodine, heated gently in a test gave off a purple vapour.(Solved)
A crystal of iodine, heated gently in a test gave off a purple vapour.
a) Write the formula of the substance responsible for the purple vapour
b) What type of bond is broken when the iodine crystal is heated gently
c) state one use of iodine
Date posted: February 2, 2017. Answers (1)
- In terms of structure and bonding, explain the following observations(Solved)
In terms of structure and bonding, explain the following observations
a) The melting point of aluminium is higher than that of sodium:
b) Melting point of chlorine is lower than that of sulphur
Date posted: February 2, 2017. Answers (1)
- Other than their location in the atom, name two other differences between an electron and a proton(Solved)
Other than their location in the atom, name two other differences between an electron and a proton
Date posted: February 2, 2017. Answers (1)
- In terms of structure and bonding, explain why the melting point of oxygen is much lower than that of sodium.(Solved)
In terms of structure and bonding, explain why the melting point of oxygen is much lower than that of sodium.
Date posted: February 2, 2017. Answers (1)
- Both chlorine and iodine are halogens (a) what are halogens(Solved)
Both chlorine and iodine are halogens
a) what are halogens
b) In terms of structure and bonding, explain why the boiling point of chlorine is lower than that of iodine
Date posted: February 2, 2017. Answers (2)
- Distinguish between a covalent bond and co-ordinate bond(Solved)
Distinguish between a covalent bond and co-ordinate bond.
Date posted: February 2, 2017. Answers (1)
- The atomic numbers of elements C and D are 19 and 9 respectively. State and explain the electrical conductivity of the compound CD in(Solved)
The atomic numbers of elements C and D are 19 and 9 respectively. State and explain the electrical conductivity of the compound CD in
a) Solid state
b) Aqueous state
Date posted: February 2, 2017. Answers (1)
- With reference to iodine, distinguish between covalent bonds and Van Der Waals forces(Solved)
With reference to iodine, distinguish between covalent bonds and Van Der Waals forces.
Date posted: February 2, 2017. Answers (1)
- 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)