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

Come si chiama il passaggio da liquido a gas?

1. ACongelamento
2. BCondensazione
3. CFusione
4. DEvaporazione (vaporizzazione)

Which is a sign that a chemical reaction may have taken place?

1. ASugar dissolves completely when stirred into water
2. BA block of wax melts when it is heated
3. CA gas is produced when two liquids are mixed
4. DWater freezes into ice when put in a freezer

What does the coefficient 3 in "3H₂O" mean?

1. AEach water molecule has three oxygen atoms
2. BEach molecule of water contains three hydrogen atoms
3. CWater has a charge of 3
4. DThere are three molecules (or moles) of water

On an energy diagram, the products are at a lower energy than the reactants. What kind of reaction is shown?

1. AExothermic
2. BReversible only
3. CEndothermic
4. DNuclear

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

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

What is the formula of the hydroxide ion?

1. AH₃O⁺
2. BOH⁺
3. CO²⁻
4. DOH⁻

The true volume in a flask is 10,0 mL. A student measures it three times and gets 8,1 mL, 8,1 mL and 8,2 mL. How are these results best described?

1. ANeither accurate nor precise
2. BBoth accurate and precise
3. CAccurate but not precise
4. DPrecise but not accurate

Which approach best reduces a health worker's exposure to ionising radiation?

1. ALimit the time near the source, increase the distance and use shielding
2. BStand closer to the source so the job is finished sooner and exposure is shorter
3. CWork faster without any shielding
4. DRely only on wearing gloves