Post Utme Chemistry Past Questions and Answers

Question 1146:

The decreasing order of the magnitude of energy changes is ____________

A. Phase, chemical, nuclear
B. Chemical, nuclear, phase
C. Nuclear, phase, chemical
D. Nuclear, chemical, phase

Question 1147:

$0.92g$ of ethanol raised the temperature of $100g$ of water from $298K$ to $312.3K$ when burned completely. What is the heat of combustion of ethanol?
$[C=12;H=$ $1;O=16$; specific heat capacity of water $\text{Extra left or missing right}$

A. $+300kJmol$
B. $+3000kJmol$
C. $-300kJmol$
D. $-3000kJmol$

Question 1148:

The highest level of molecular disorderliness is found in ____________

A. Ice at $-{10}^{\circ }C$
B. Water at ${100}^{\circ }C$
C. Steam at ${100}^{\circ }C$
D. Ice at $0^{\circ }C$

Question 1149:

A reaction is spontaneous at all temperature if ____________

A. $\mathrm{\Delta }G=0$
B. $\mathrm{\Delta }G>0$
C. $\mathrm{\Delta }S<0$ and $\mathrm{\Delta }H>0$
D. $\mathrm{\Delta }S>0$ and $\mathrm{\Delta }H<0$

Question 1150:

Which of the following reactions of marble with $100c{m}^3$ of $0.100$ moldm${}^3$. HCl is fastest?

A. $5g$ of marble lump at ${50}^{\circ }C$
B. $5g$ of marble powder at ${50}^{\circ }C$
C. $5g$ of marble powder at ${25}^{\circ }C$
D. $5g$ of marble lump at ${25}^{\circ }C$