Робочий аркуш «Хімія для вступних іспитів на медсестринство» з відповідями

A food Calorie (written with a capital C) equals which amount of energy?

1. A1 joule
2. B1 kilocalorie
3. C1 calorie
4. D1 kilojoule (1000 J)

Як називається перехід із рідкого стану в газоподібний?

1. AПлавлення
2. BКонденсація
3. CЗамерзання
4. DВипаровування

What is radioactivity?

1. AThe glow produced by any hot object
2. BThe release of heat and light when fuels burn in air
3. CThe release of radiation by unstable atomic nuclei
4. DThe flow of electrons through a metal wire

A red blood cell is placed in pure water (a hypotonic solution). What happens?

1. AWater leaves the cell, which shrinks and wrinkles
2. BNothing happens to the cell
3. CWater enters the cell, which swells and may burst
4. DSalt enters the cell, which shrinks

What charge do group 16 elements such as oxygen and sulfur usually have as ions?

1. A2+
2. B1−
3. C2−
4. D6+

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. C133%
4. D5%

Pepsin digests protein in the stomach at about pH 2, but it stops working once food moves into the small intestine, where the pH is higher. Why?

1. APepsin only works on fats in the small intestine
2. BThe change in pH alters the shape of pepsin's active site
3. CPepsin is used up completely in the stomach, just like a reactant
4. DThe small intestine is too cold for any enzyme

A catalyst is added to an exothermic reaction. How does the energy diagram change?

1. AThe products end up at a lower energy, so more heat is released
2. BThe reactants start at a higher energy
3. CThe reaction becomes endothermic
4. DThe peak is lower, but the energy of reactants and products stays the same