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

Каков pH чистой воды при 25 °C?

1. A0
2. B1
3. C14
4. D7

According to the Arrhenius definition, what does a base produce in water?

1. AHydrogen ions (H⁺)
2. BChloride ions (Cl⁻)
3. CCarbonate ions (CO₃²⁻)
4. DHydroxide ions (OH⁻)

What is osmosis?

1. AThe movement of solute particles against a gradient using energy
2. BThe breaking of a solid into ions
3. CThe movement of water across a semipermeable membrane
4. DThe dissolving of a gas in a liquid

Water has a high specific heat capacity. How does this help the human body?

1. AIt allows oxygen to dissolve in water more easily
2. BIt makes water a poor solvent for salts
3. CIt helps keep body temperature stable
4. DIt makes the blood more acidic

Why do group 1 metals such as sodium react so easily?

1. AThey easily gain one extra electron
2. BTheir nuclei contain no neutrons
3. CThey have a full outer shell of electrons
4. DThey have one outer electron that is easily lost

Why does stirring help a solid dissolve faster?

1. AIt turns the solid into a liquid
2. BIt raises the temperature of the solvent by friction a great deal
3. CIt brings fresh solvent into contact with the solid's surface
4. DIt increases the amount of solute that can dissolve in total

Using PV = nRT with R = 0,082 L·atm/(mol·K), how many moles of gas are in 24,6 L at 1 atm and 300 K?

1. A1 mol
2. B2 mol
3. C300 mol
4. D0,5 mol

An element has the electron arrangement 2, 8, 8, 2. Where is it on the periodic table?

1. AGroup 8, period 2
2. BGroup 4, period 2
3. CGroup 2, period 2
4. DGroup 2, period 4