Scheda di esercizi di Chimica per i test di ammissione a infermieristica con soluzioni

What is absolute zero?

1. A0 °C, the point at which pure water freezes into ice
2. B−100 °C, the coldest temperature on Earth
3. C0 K, about −273 °C, the lowest possible temperature
4. D0 °F, the temperature of a salt and ice mixture

What is an electrolyte?

1. AA substance that forms ions and conducts electricity when dissolved in water
2. BA gas that dissolves in blood
3. CA metal that conducts electricity as a solid
4. DA substance that dissolves as whole molecules without forming any ions

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

1. Akg
2. BmL/g
3. Cg/mL
4. Dg·mL

A red blood cell is placed in a concentrated (hypertonic) salt solution. What happens?

1. AThe cell stays the same size and shape
2. BSalt leaves the cell, which swells
3. CWater enters the cell, which swells and may burst
4. DWater leaves the cell, which shrinks

Secondo la teoria cinetico-molecolare, che cosa misura la temperatura?

1. AL'energia cinetica media delle particelle
2. BLa dimensione del contenitore
3. CLa massa di ogni particella
4. DIl numero totale di particelle

Sulfur has 16 electrons. In which period of the periodic table is it?

1. APeriod 2
2. BPeriod 3
3. CPeriod 6
4. DPeriod 16

Ethanol (CH₃CH₂OH) and dimethyl ether (CH₃OCH₃) have the same formula, C₂H₆O, but ethanol boils at a much higher temperature. Why?

1. ADimethyl ether is ionic and ethanol is covalent
2. BEthanol has an O–H group, so its molecules form hydrogen bonds with each other
3. CEthanol has more carbon atoms
4. DEthanol molecules are heavier than dimethyl ether molecules

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