Question 776:

• JAMB 1993

Which of the following substances is a mixture?

A. Sulphur powder
B. Bronze
C. Distilled water
D. Ethanol

Question 777:

• JAMB 1993

A balanced chemical equation obeys the law of?

A. Conservation of mass
B. Difinite proportions
C. Multiple proportions
D. Conservation of energy

Question 778:

• JAMB 1993

How many moles of oxygen molecules would be produced from the decomposition of 2.50 moles of potassium trioxochlorate (V)?

A. 2.50
B. 3.50
C. 3.75
D. 7.50

Question 779:

• JAMB 1993

For iodine crystals to sublime on heating, the molecules must acquire energy that is?

A. Less than the forces odf attraction in the solid
B. Equal to the forces of attraction in th solid
C. Necessary to melt the solid
D. Greater than the forces of attraction in both the solid and the liquid phases

Question 780:

• JAMB 1993

An element, E, has the electronic configuration 1s²2s²2p⁶3s²p³. The reaction of E with a halogen X can give?

A. EX₃ and EX₅
B. EX₃ only
C. EX₅ only
D. EX₂ and EX₃