Химия для вступительных экзаменов на сестринские программы: лист заданий с ответами

What are the building blocks of carbohydrates such as starch?

1. AMonosaccharides (simple sugars) such as glucose
2. BAmino acids
3. CFatty acids joined to a glycerol molecule
4. DNucleotides

Which form of sugar dissolves fastest in a cup of tea?

1. AA sugar cube
2. BA large lump of rock sugar
3. CAll forms dissolve at the same rate
4. DGranulated sugar

Which element exists naturally as diatomic molecules (two atoms joined together)?

1. AHelium
2. BIron
3. COxygen
4. DSodium

A reaction has a theoretical yield of 20 g, but only 15 g of product is collected. What is the percent yield?

1. A25%
2. B75%
3. C5%
4. D133%

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

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

Какова молярная масса воды (H = 1 г/моль, O = 16 г/моль)?

1. A17 г/моль
2. B10 г/моль
3. C32 г/моль
4. D18 г/моль

Frying an egg turns the clear egg white solid and white. What happens to the proteins?

1. AThey are denatured: their shape changes, but the peptide bonds stay intact
2. BThey are converted into fats
3. CThey are burned to carbon dioxide and water
4. DThey are hydrolysed, so the peptide bonds break into separate amino acids

Образец содержит 3,01 × 10²³ молекул воды. Сколько это молей?

1. A3,01 моль
2. B0,5 моль
3. C1,81 моль
4. D2 моль