Separation of mixtures and purification of chemical substances - Jamb Chemistry Past Questions and Answers

Question 91:

• JAMB 2013

The presence of an impurity in substance will cause the melting point to

A. Be zero
B. Reduce
C. Increase
D. Be stable

Question 92:

• JAMB 2013

The presence of an impurity in substance will cause the melting point to

A. Be zero
B. Reduce
C. Increase
D. Be stable

Question 93:

• JAMB 2013

What volume of carbon (ll) oxide is produced by reacting excess carbon with 10 dm³ of oxygen?

A. 5 dm ³
B. 20 dm ³
C. 15 dm ³
D. 10 dm ³

Question 94:

• JAMB 2013

An example of a hygroscopic substance is

A. CuO _(S).
B. MgCL_2(S).
C. CaCL_2(S).
D. NaOH_(S).

Question 95:

• JAMB 2013

10.0 dm³ of water was added to 2.0 mol dm^-3 of 2.5dm³ solution of HCl. What is the concentration of the final solution in mol dm^-3?

A. 0.4
B. 8.0
C. 2.0
D. 0.5