Chemia na egzaminy wstępne na pielęgniarstwo: karta pracy z odpowiedziami

Which gas is needed for a fuel to burn (combustion)?

1. AOxygen
2. BHelium
3. CNitrogen
4. DCarbon dioxide

What are the units of molarity?

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

What does the law of conservation of mass state?

1. AThe mass of products is always greater than the mass of reactants
2. BMass is neither created nor destroyed in a chemical reaction
3. CMass is lost as heat in every reaction
4. DGases have no mass

What is 380 mmHg in atmospheres?

1. A380 atm
2. B0,38 atm
3. C2 atm
4. D0,5 atm

Why does stirring help a solid dissolve faster?

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

Which coefficients balance __KClO₃ → __KCl + __O₂?

1. A2, 2, 3
2. B1, 1, 3
3. C1, 1, 1
4. D2, 1, 3

Why is incomplete combustion of fuel in a poorly ventilated room dangerous?

1. AIt produces water vapour, which is toxic
2. BIt produces extra oxygen, which damages the lining of the lungs over time
3. CIt produces carbon monoxide, which binds to haemoglobin and blocks oxygen transport
4. DIt produces nitrogen, which replaces oxygen in the blood

A mixture contains sand, salt and water. Which sequence separates all three?

1. AUse a magnet to remove the salt, then filter the sand
2. BEvaporate all the water first, then filter the salt away from the dry sand
3. CFilter to remove the sand, then distil the filtrate to collect water and leave salt
4. DDistil first to remove the sand, then filter out the salt