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

How many moles of oxygen atoms are in 1 mole of carbon dioxide, CO₂?

1. A3
2. B2
3. C0,5
4. D1

What does the law of conservation of mass state?

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

In a chemical equation, what does the symbol (aq) after a formula mean?

1. AA solid
2. BA gas
3. CA pure liquid
4. DDissolved in water

Nitric acid (HNO₃) reacts with potassium hydroxide (KOH). Which salt forms?

1. APotassium nitrate, KNO₃
2. BPotassium nitrite, KNO₂
3. CNitrogen hydroxide, NOH
4. DPotassium hydride, KH

Magnesium forms Mg²⁺ ions and oxygen forms O²⁻ ions. What is the formula of magnesium oxide?

1. AMgO₂
2. BMgO
3. CMg₂O
4. DMg₂O₂

За сталої температури об'єм газу зменшують удвічі. Що відбувається з його тиском?

1. AВін зменшується вдвічі
2. BВін залишається незмінним
3. CВін подвоюється
4. DВін стає в чотири рази меншим

Sugar is heated in a pan. Which observation shows that a chemical change, not just a physical change, has happened?

1. AThe crystals become smaller when crushed
2. BIt melts into a clear, runny liquid that sets again when it cools
3. CIt turns black and gives off water vapour, leaving a solid that is no longer sweet
4. DIt gets hot to the touch

Many ethene (C₂H₄) molecules join together to form poly(ethene), a plastic. What type of reaction is this?

1. ACombustion, in which ethene reacts with oxygen
2. BCondensation polymerisation, in which a water molecule is released at each new link
3. CAddition polymerisation, in which the C=C double bonds open up to link the monomers
4. DHydrolysis, in which water breaks each monomer apart