BUK Chemistry 2020/2021 Past Questions

Practice each question, then open it to see the full details.

How many grams of hydrogen gas will be liberated when 6g of magnesium ribbon dissolves in 500cm³ of 6M HCl? [Mg = 24, H = 1, Cl = 35.5]

A.0.2g
B.0.7g
C.0.5g
D.0.3g

Metal X will be above metal Y in the activity series if X

A.displaces ions of Y from solution
B.has a higher relative atomic mass than Y
C.has a higher melting point than Y
D.has a higher boiling point than Y

Which of the following exhibits isotopy?

A.But-1-ene and but-2-ene
B.carbon and hydrogen
C.Oxygen and ozone
D.Hydrogen and deuterium

The oxidation state of oxygen in tetraoxosuphate (iv)acid is

A.-4
B.+4
C.-2
D.+2

Chlorine, consisting of two isotopes of mass numbers 35 and 37, has an atomic mass of 35.5. The relative abundance of the isotope of mass number 37 is

A.20
B.25
C.50
D.75

The symbol of an isotope is $^{57}_{26}Fe$ Which gives the correct numbers of protons, neutrons and electrons in this atom?

A.26 proton, 26 neutrons, 31 electrons
B.31 proton, 26 neutrons, 31 electrons
C.31 proton, 31 neutrons, 26 electrons
D.26 proton, 31 neutrons, 26 electrons

Which of the following will not give precipitate with ammoniacal AgNO₃ solution?

A.CH₃C≡CCH₃
B.HC≡CH
C.CH₃C≡CH
D.CH₃CH₂C≡CH

Bond dissociation energy of 500 KJ mol^-1 may be assigned to

A.ionic bonding
B.covalent bonding
C.hydrogen bonding
D.metallic bonding

Alkanoic acids are weak acids and ionises in solution to give:

A.R⁺ + COOH
B.RCOO + H
C.RCO + OH
D.RCOOH + OH

Which following is true about the trend Down the group 7 Halogens with increase in atomic number?

A.The reactivity increases
B.The melting point decreases
C.The atoms get smaller
D.The boiling point increases