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

A cleaning solution has a pH of 12. How is it described?

1. AStrongly basic
2. BStrongly acidic
3. CWeakly acidic
4. DNeutral

What does the octet rule state?

1. AAn atom can form a maximum of 8 covalent bonds
2. BAtoms tend to gain, lose or share electrons to get 8 outer electrons
3. CEvery stable molecule contains exactly 8 atoms
4. DEvery stable atom has exactly 8 protons in its nucleus

What range does the common pH scale cover?

1. A0 to 14
2. B−7 to +7
3. C0 to 100
4. D1 to 10

A solution has a pH of 2. What is its hydrogen ion concentration?

1. A1 × 10⁻¹² mol/L
2. B2 mol/L
3. C1 × 10² mol/L
4. D1 × 10⁻² mol/L

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

1. AExothermic
2. BNuclear
3. CEndothermic
4. DReversible only

How is 0,00045 written in scientific notation?

1. A4,5 × 10⁴
2. B4,5 × 10⁻⁴
3. C4,5 × 10⁻³
4. D4,5 × 10⁻⁵

What is a triglyceride made of?

1. AOne fatty acid joined to three glycerol molecules
2. BThree amino acids joined by peptide bonds
3. CThree glucose molecules joined together
4. DOne glycerol molecule joined to three fatty acids

Which statement correctly distinguishes a scientific law from a scientific theory?

1. ALaws apply only to chemistry, theories only to biology
2. BA law describes what happens; a theory explains why it happens
3. CA law is only a guess, while a theory is a proven fact
4. DA theory becomes a law once it is proved