CHEMISTRY 9

Which ion has the most shells that contain electrons?

• $Al^{3+\ \ \ \ \ }\ \ \ \$

• $Be^{2+\ \ \ \ \ }$

• $N^{3-\ \ }$

• $S^{2-}\ \ \ \$

Nucleon number of an tom of element X is 7 and its proton number is 3. Which statement about an atom of X is correct?

• It is in Group 3 of the Periodic Table

• It is in Group 7 of the Periodic Table

• The total number of protons and electrons is 6

• The total number of protons and neutrons is 10.

The relative atomic mass of naturally occurring chlorine is not a whole number. What is the reason for this?

• Chlorine atoms can have different numbers of neutrons.

• Chlorine is unstable

• Naturally occurring chlorine cannot be obtained pure

• The mass of electrons has been included.

Which statement about an atom is correct?

• Each element has only one nucleon (mass) number

• The nucleon (mass) number can be less than proton (atomic) number

• The nucleon (mass) number can be equal the proton (atomic) number

• The number of neutrons never equals the number of electrons.

What has a mass equal to that of one mole of water?

• $24\ dm^3\$ of water
  

• one mole of steam

• one molecule of water

• two moles of hydrogen molecules and one mole of oxygen molecules

What is the mass of magnesium which completely reacts with $250\ cm^3\$  of 1.0  $mol\ dm^{-1}\ \$  sulphuric acid?

• 6 g

• 12 g

• 48 g

• 96 g 

A volume of ethane,  $C_2H_6,\$  at r.t.p. has a mass of 20 g.

What is the mass of an equal volume of propene,  $C_3H_6,$  at r.t.p.?

• 20 g

• 21 g

• 28 g

• 42 g

What is the ratio of the volume of 2 g of hydrogen to the volume of 16 g of methane, both volume at r.t.p.?

• 1 to 1

• 1 to 2

• 1 to 8

• 2 to 1

What is the mass of aluminium in 204 g of aluminium oxide, $Al_2O_3?\$  

• 26 g

• 27 g

• 54 g

• 108 g

Which quantity is the same for one mole of ethanol and one mole of ethane?

• mass

• number of atoms

• number of molecules

• volume at r.t.p.