Chemistry for nursing entrance exams worksheet with answers

Which property is typical of nonmetals?

1. AThey are shiny and easily bent into wires
2. BThey easily lose electrons to form positive ions
3. CThey are all solids at room temperature
4. DThey are poor conductors of heat and electricity

A neutral atom has 11 protons. How many electrons does it have?

1. A10
2. B22
3. C12
4. D11

Which unit is commonly used for the density of a liquid?

1. Ag/mL
2. Bkg
3. Cg·mL
4. DmL/g

What is the formula of aluminium oxide, made of Al³⁺ and O²⁻ ions?

1. AAlO₃
2. BAl₃O₂
3. CAlO
4. DAl₂O₃

Why is a carbon dioxide extinguisher effective on many fires?

1. ACO₂ is denser than air and pushes oxygen away from the fire
2. BCO₂ adds oxygen to cool the flames
3. CCO₂ reacts chemically with the fuel to make it non-flammable
4. DCO₂ is a liquid that soaks into the fuel

Why is a water molecule polar?

1. AWater has ionic bonds between hydrogen and oxygen
2. BOxygen pulls the shared electrons more strongly, and the molecule is bent
3. CWater molecules are straight, with both hydrogens on one line
4. DHydrogen is more electronegative than oxygen

A solution of acetic acid conducts electricity only weakly, while hydrochloric acid of the same concentration conducts strongly. Why?

1. AAcetic acid does not dissolve in water at all
2. BAcetic acid forms more ions than hydrochloric acid does
3. CAcetic acid only partly ionises, so it forms fewer ions
4. DHydrochloric acid contains metal atoms

CO₂ in blood forms carbonic acid: CO₂ + H₂O ⇌ H₂CO₃ ⇌ H⁺ + HCO₃⁻. An anxious patient hyperventilates and breathes off extra CO₂. What happens to blood pH?

1. AIt stays exactly 7.40, because CO₂ does not affect pH
2. BIt rises, because less CO₂ means fewer H⁺ ions
3. CIt falls, because less CO₂ means more H⁺ ions
4. DIt falls, because oxygen is an acid