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

What is radioactivity?

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

О чём говорит атомный номер элемента?

1. AОб общем числе протонов и нейтронов в ядре
2. BО числе атомов в одном моле элемента
3. CО числе протонов в каждом атоме
4. DО числе нейтронов в каждом атоме

What are the units of molarity?

1. AGrams of solute per litre of solution (g/L)
2. BGrams of solute per 100 g of solution
3. CMoles of solute per kilogram of the solvent used
4. DMoles of solute per litre of solution (mol/L)

In 2KClO₃ → 2KCl + 3O₂, how many moles of O₂ form from 4 mol of KClO₃?

1. A3 mol
2. B8 mol
3. C6 mol
4. D4 mol

What is the mass of 0,5 mol of NaCl (molar mass 58,5 g/mol)?

1. A117 g
2. B58,5 g
3. C29,25 g
4. D0,5 g

For the gas reaction N₂ + 3H₂ ⇌ 2NH₃, what is the effect of increasing the pressure?

1. AThe equilibrium shifts to the left, toward N₂ and H₂
2. BThe NH₃ breaks down completely
3. CThere is no effect on the equilibrium
4. DThe equilibrium shifts to the right, toward NH₃

The true volume in a flask is 10,0 mL. A student measures it three times and gets 8,1 mL, 8,1 mL and 8,2 mL. How are these results best described?

1. APrecise but not accurate
2. BAccurate but not precise
3. CBoth accurate and precise
4. DNeither accurate nor precise

Why does a burn from steam at 100 °C usually cause more damage than one from liquid water at 100 °C?

1. ASteam particles are hotter than water particles at the same reading
2. BSteam carries dissolved acid that damages the skin
3. CSteam releases a large amount of extra energy as it condenses on the skin
4. DLiquid water cannot pass any of its heat to the skin