Chemia na egzaminy wstępne na pielęgniarstwo: karta pracy z odpowiedziami

In a chemical reaction, what is the limiting reactant?

1. AThe reactant that is left over at the end
2. BThe reactant with the largest mass
3. CThe reactant that runs out first and stops the reaction
4. DThe catalyst that controls the speed

What is a dilute solution?

1. AOne with a large amount of solute in a little solvent
2. BOne in which the solute has reacted with the solvent
3. COne with no solvent at all
4. DOne with a small amount of solute in a lot of solvent

What does the coefficient 3 in "3H₂O" mean?

1. AEach water molecule has three oxygen atoms
2. BThere are three molecules (or moles) of water
3. CEach molecule of water contains three hydrogen atoms
4. DWater has a charge of 3

A reaction has ΔH = −890 kJ/mol. What does the negative sign tell you?

1. AThe reaction is endothermic
2. BThe reaction is at equilibrium
3. CThe reaction is exothermic
4. DThe reaction needs a catalyst

Jaka jest masa molowa wody (H = 1 g/mol, O = 16 g/mol)?

1. A10 g/mol
2. B17 g/mol
3. C32 g/mol
4. D18 g/mol

How does an antacid tablet relieve heartburn caused by excess stomach acid?

1. AA weak base in it neutralises some of the acid
2. BIt coats the stomach and stops all acid production
3. CAn acid in it lowers the stomach pH further
4. DIt turns the acid into a gas that is absorbed

Why is it easier to remove the outer electron from a potassium atom than from a lithium atom?

1. APotassium's outer electron is in a full shell
2. BPotassium has fewer protons, so its nucleus pulls much more weakly on every electron
3. CLithium has more electron shells than potassium
4. DPotassium's outer electron is farther from the nucleus and more shielded by inner electrons

10 g substancji rozpuszcza się w wodzie, dając 250 mL roztworu. Jakie jest jej stężenie w g/L?

1. A0,04 g/L
2. B2,5 g/L
3. C25 g/L
4. D40 g/L