Užduočių lapas tema Chemija slaugos stojamiesiems egzaminams su atsakymais

What does organic chemistry study?

1. ACompounds made of metals
2. BOnly compounds found in plants
3. COnly the noble gases
4. DCompounds based on carbon

Which element exists naturally as diatomic molecules (two atoms joined together)?

1. AIron
2. BHelium
3. COxygen
4. DSodium

Which method separates two liquids with different boiling points, such as alcohol and water?

1. ADistillation
2. BFiltration
3. CSieving
4. DUsing a magnet

Kurie koeficientai subalansuoja __N₂ + __H₂ → __NH₃?

1. A1, 3, 1
2. B2, 3, 2
3. C1, 1, 1
4. D1, 3, 2

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

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

Uranium-235 and uranium-238 both have 92 protons. How many more neutrons does an atom of uranium-238 have?

1. A146
2. B3
3. C0
4. D92

A liquid has a density of 1,2 g/mL. What is the mass of 250 mL of this liquid?

1. A251,2 g
2. B208 g
3. C30 g
4. D300 g

Carbon-14 (atomic number 6) decays by emitting a beta particle. What does it become?

1. ANitrogen-14
2. BNitrogen-15
3. CCarbon-13
4. DBoron-14