eg:
Some foods contain ‘hydrogenated vegetable oils’. These are unsaturated fats that have been
converted to saturated fats.
Which property of the fats will have changed?
A Their hydrocarbon chains will fit together more closely.
B Their solubility in water will increase.
C They will have more double bonds in their molecules.
D They will remain liquid at room temperature.
题中提到，植物油为不饱和脂，转化为饱和脂类之后会发生怎么的性质变化。 生活中我们应该会看到花生油或大豆油都是液态的，因为它们都不饱和;而猪油饱和程度大，所以常温下为固态。因此由不饱和脂转化为饱和脂状态应该更接近于固态，故此D错，其固化程度高了，水溶性肯定不会提高，因此B错。而不饱和程度其实是由其不饱和键决定的(双键或三键)，不饱和程度高，其双键应该多，因此C错。最后则只能选A，因为饱和程度大意味着氢多了，因此链应该更近了。
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