Chemistry for nursing entrance exams worksheet with answers

What is the change from a liquid to a solid called?

1. AMelting
2. BFreezing
3. CEvaporation
4. DCondensation

What kind of carbon–carbon bonds do alkanes contain?

1. AOnly single bonds
2. BAt least one double bond
3. CAt least one triple bond
4. DIonic bonds

Salt water is an example of which kind of matter?

1. AA compound
2. BA heterogeneous mixture
3. CA pure element
4. DA homogeneous mixture (solution)

How can you get solid salt back from salt water?

1. AFilter the solution
2. BEvaporate the water
3. CUse a magnet
4. DFreeze the solution and lift out the salt

Drops of water form on the outside of a glass of ice water. Where does this water come from?

1. AWater leaks through tiny holes in the glass
2. BThe ice evaporates through the glass
3. CThe glass releases water when it gets cold
4. DWater vapour in the air condenses on the cold glass

A reaction has ΔH = −890 kJ/mol. What does the negative sign tell you?

1. AThe reaction is exothermic
2. BThe reaction is endothermic
3. CThe reaction needs a catalyst
4. DThe reaction is at equilibrium

Pepsin digests protein in the stomach at about pH 2, but it stops working once food moves into the small intestine, where the pH is higher. Why?

1. APepsin is used up completely in the stomach, just like a reactant
2. BThe change in pH alters the shape of pepsin's active site
3. CPepsin only works on fats in the small intestine
4. DThe small intestine is too cold for any enzyme

A student tests whether water temperature affects how fast sugar dissolves. Which set of factors should be kept the same in every trial?

1. AThe water temperature and the dissolving time
2. BThe mass of sugar, the type of sugar, the volume of water and the amount of stirring
3. CNothing, because changing several factors at once gives more useful data
4. DOnly the colour of the cup