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

What range does the common pH scale cover?

1. A−7 to +7
2. B1 to 10
3. C0 to 100
4. D0 to 14

Quale di questi è un cambiamento fisico?

1. AL'acqua che bolle e diventa vapore
2. BIl ferro che arrugginisce
3. CIl pane tostato fino a dorarsi
4. DIl latte che inacidisce

What is an empirical formula?

1. AA drawing of how the atoms are bonded
2. BThe mass of one mole of a compound
3. CThe simplest whole-number ratio of atoms in a compound
4. DThe actual number of each atom in one molecule

Which element has chemical properties most similar to calcium?

1. APotassium
2. BScandium
3. CCarbon
4. DMagnesium

How does a mixture of iron filings and sulfur powder differ from the compound iron sulfide?

1. AThe mixture can be separated physically, for example with a magnet
2. BThe mixture has a fixed ratio of iron to sulfur
3. CThe compound keeps the magnetic properties of iron
4. DThe mixture is formed by a chemical reaction between the two elements

What is the molar mass of calcium carbonate, CaCO₃ (Ca = 40, C = 12, O = 16 g/mol)?

1. A100 g/mol
2. B68 g/mol
3. C84 g/mol
4. D116 g/mol

What is the formula of iron(III) chloride?

1. AFe₃Cl
2. BFeCl₃
3. CFe₂Cl₃
4. DFeCl₂

Gently heating DNA separates its two strands, but each strand stays in one piece. Why?

1. AHeat converts DNA into a protein
2. BThe strands are held together by weak hydrogen bonds, while each strand's backbone is covalent
3. CThe two strands are joined by ionic bonds that melt first
4. DEach strand is held together by hydrogen bonds, while the two strands are joined by covalent bonds